Anneke Haagen: computer consultant in Ann Arbor, Michigan, by Susan Holtzer

Hagen: government agent in the USA, by Kay Hooper

Clark Hager: FBI-trained profiler working in North Carolina, by Jeff Pate

Annabelle Haggerty: FBI agent and true psychic, and Samantha Brennan, fake psychic, in Los Angeles, California, by Kris Neri

Leo Haggerty: rough and tough private investigator in Washington DC, by Benjamin Schutz

Lindy Haggerty: rehearsal director and retired dancer, by Shelley Freydont

Sam Haine: agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives, in the US Department of Homeland Security, by Bruce Cook

Jack Haldean: former Royal Flying Corps pilot and mystery writer, in early 1920s England, by Dolores Gordon-Smith

Max Hale: reluctant detective, by George Harmon Coxe

Satan Hall: police detective in New York City, by Carroll John Daly

Lucas Hallam: stuntman and former Texas Ranger, in the 1920s, by Livia J. Washburn

Mickey Haller: lawyer in Los Angeles, California, by Michael Connelly

Mike Haller: private eye specializing in missing persons in San Francisco, California, by Max Byrd

Perdita Halley, a concert pianist, and Alexander von Reisden, a young Austrian biochemist, first in pre-WWI Boston, Massachusetts, and then Paris, France, by Sarah Smith

Sid Halley: injured steeplechase jockey turned private eye in England, by Dick Francis

Tommy Hambledon: master spy for England, between the World Wars and after, by Manning Coles

Neil Hamel: attorney and investigator, in Albuquerque, New Mexico, by Judith Van Gieson

Mike Hammer: private eye in New York City, by Mickey Spillane

Blanche Hampton: detective superintendent at Scotland Yard, in London, England, by Trevor Barnes

Francis Hancock: undertaker in 1940s London, England, by Barbara Nadel

John Handford: Detective Inspector, and Detective Sergeant Khalid Ali, in Bradford, Yorkshire, England, by Lesley Horton

Arly Hanks: small-town police chief in Maggody, Arkansas, by Joan Hess

Gabe Hanna: deputy sheriff, and Cliff Lansing, a single father and part-time rancher-sheriff, in New Mexico, by Micah S. Hackler

Superintendent Hannasyde: police superintendent in England, by Georgette Heyer

Richard Hannay: ordinary fellow caught up in extraordinary events in England and Scotland, by John Buchan

Joseph Hannegan: Superintendent at Ellis Island, and Rachel Bonner, a society lady who has given up her position to help immigrants, in 1901 New York City, in the Ellis Island mysteries by Ann Stamos (Takis & Judy Iakovou)

Joe Hannibal: blue-collar private investigator based in Rockford, Illinois, by Wayne D. Dundee

Nick Hannibal: homicide detective, and Molly Rafferty, a history professor at Scattergood College, in Boston, Massachusetts, by Sophie Belfort

Claire Hanover: 40-something proprietor of a gift-basket business, in Colorado Springs, Colorado, by Beth Groundwater

Em Hansen: forensic geologist in Wyoming, by Sarah Andrews

Brian Hanson: Vietnam veteran and psychologist in a mental health clinic in Portland, Maine, by Mark Schorr

Sigrid Harald: police lieutenant in New York City, by Margaret Maron

Anne Hardaway: ghostwriter in Oceanside Heights, New Jersey, in the Jersey Shore mysteries, by Beth Sherman

Ernest Hardcastle: divisional detective inspector, head of CID for the Whitehall Division of the Metropolitan Police, during World War I, in London, England, by Graham Ison

Dick Hardesty: a gay detective, by Dorien Grey

Stella Hardesty: a 50-year-old widow who suffered domestic violence, running a sewing shop and helping other abused women, in a small town in Missouri, by Sophie Littlefield

Wil Hardesty: Vietnam Vet private investigator, in Los Angeles, California, by Richard Barre

Art Hardin: retired colonel, now a low-keyed private investigator in Grand Rapids, Michigan, by Robert E. Bailey

Harding: an unlicensed private investigator in Chicago, Illinois, by John Wessel

Cliff Hardy: private investigator in Australia, by Peter Corris

Dismas Hardy: ex-cop bartender and ex-Assistant District Attorney turned defense attorney, and Abe Glitsky, a black, Jewish cop, in San Francisco, California, by John Lescroart

Wilhelmina “Bil” Hardy: baby dyke in Cowslip, Idaho, by Joan Opyr

Annabelle Hardy-Maratos: deaf president of a large Miami security firm, and Dave the Monkeyman, her sidekick and main ASL signer, in Miami, Florida, by Hialeah Jackson (Polly Whitney)

Mary Minor Haristeen: postmistress and her cat, Mrs. Murphy, in Crozet, by Rita Mae Brown

Costas Haritos: former prison guard, now inspector in the CID in Athens, Greece, by Petros Markaris

Hawthorne Albert Harker: an investigative reporter, by Marc Olden

John Harland: in New York City, by Rae Foley

Paul Harley: by Sax Rohmer

Fran Harman: Detective Chief Superintendent nearing retirement, in Kent, England, by Judith Cutler

Steve Harmas: by James Hadley Chase

Albenia “Benni” Harper: ex-rancher and folk art museum curator in San Celina, California, by Earlene Fowler

Goodwin Harper: food consultant in London, England, by Peter King

Sam Harper: homicide detective in Chandler, Massachusetts, by Marta Stephens

Tilda Harper: celebrity journalist based in Boston, Massachusetts, in the “Where Are They Now?” mysteries by Toni L.P. Kelner

Colin Harpur: detective chief superintendent, and Desmond Iles, assistant chief constable, in an English seaport by Bill James

Sally Harrington: television journalist in Connecticut, by Laura Van Wormer

Leah Harris: police detective sergeant, in Seattle, Washington by Michael A. Hawley

Paul Harris: Scot with a heavy equipment business in Singapore by Gavin Black (Oswald Morris Wynd)

Meg Harris: escapee from Toronto and a failed marriage who retreats to the remote wilderness of West Quebec, Canada, where she fights any injustice, by R.J. Harlick

Chip Harrison by Lawrence Block

Richard Harrison: retired intelligence officer, now working for Canterbury Cathedral, in England, by Michael David Anthony

Ashlyn Hart, Craig Nolan, and Tain, police constables in Vancouver, British Columbia, Canada, by Sandra Ruttan

Olivia Hart: female bodybuilder and officer, and Francisco (Frank) Leal, a half-Hispanic sergeant with the Cook County Sheriff’s Department, in Chicago, Illinois, by Michael A. Black

Beth Hartley: attorney running a legal research firm, in Milwaukee, Wisconsin, by Kathleen Anne Barrett

Scot Harvath: ex-Navy Seal, Secret Service agent, and counter-terrorism operative working all over the world, by Brad Thor

Priam Harvey: racetrack journalist, and Campbell Young, a racetrack-loving homicide detective, later a private investigator, mostly in Toronto, Ontario, Canada, by J.D. Carpenter

Ellie Haskell: interior decorator, Ben Haskell, a writer and chef, and occasionally Hyacinth and Primrose Tramwell, a pair of dotty sisters and owners of the Flowers Detection Agency, by Dorothy Cannell

Vejay Haskell: Pacific Gas & Electric meter reader in northern California, by Susan Dunlap

Dell Hassler and William “Shark” Morgan: police detectives in Hilton Head, Beaufort County, South Carolina, by Vicky Hunnings

Frank Hastings: Sergeant (later, Lieutenant) co-commander of SFPD homicide in San Francisco, California, by Collin Wilcox

George Hastings: police lieutenant in St. Louis, Missouri, by James Patrick Hunt

Jean Hastings and her daughter, Jean Jr., of the interior design firm Designer Jeans, in Seville, Indiana, in the Interior Design mysteries by Peg Marberg

Lady Lupin (“Loops”) Lorrimer Hastings: 21-year old ditzy daughter of an earl, in fictional Glanville, eastern Sussex, England, by Joan Coggin

Stanley Hastings: actor and private investigator in New York City, by Parnell Hall

Jake Hatch: railroad detective in the USA, by Robert Campbell

Amos Hatcher: the art world’s foremost detective, by Oliver Banks

Ellie Hatcher: detective for the NYPD in New York City, by Alafair Burke

Paul Hatfield: chemistry professor and amateur ornithologist, in Wisconsin and elsewhere in the midwest, by Samuel Rogers

Ty Hauck: police lieutenant in Bridgeport, Connecticut, by Andrew Gross

Ola Haver and Ann Lindell, detectives in the Violent Crime Division, in Uppsala, Sweden, by Kjell Eriksson

Johnny Havoc: pint-sized (5'1") unlicensed private investigator, by John Jakes

Alex Hawke: British Lord, jet-setter, and free-lance secret operative out to save the free world, by Ted Bell

Hawker: by Carl Ramm (Randy Wayne White)

Alonzo Hawkin: homicide detective, and his partner Kate Martinelli, in San Francisco, California by Laurie R. King

J.D. Hawkins: wheelchair-bound mystery writer, in Boston, Massachusetts, by W.R. Philbrick

Joaquin Hawks: CIA operative of Hispanic and Native American descent, in Southeast Asia, by Bill S. Ballinger

Bill Hawley: undertaker in Cleveland, Ohio, by Leo Axler

Connor Hawthorne: lesbian mystery novelist and former district attorney, by Lauren Maddison

Helen Hawthorne: who gave up her affluent lifestyle for a series of minimum-wage jobs in Florida, in the Dead End Job series, by Elaine Viets

Matilda Haycastle: office temporary worker, in Brussels, Belgium, by Michele Bailey

Stuart Haydon: homicide detective in Houston, Texas, by David L. Lindsey

Lucinda Hayes: attorney and the director of the Boulder County Rape Crisis Center, in Boulder County, Colorado, by Marianne Wesson

Julie Hayes: actress turned gossip columnist and fortune teller, in New York City, by Dorothy Salisbury Davis

Karen Hayes: staff lawyer for Shoreview Memorial Hospital in Illinois, by Michael Biehl 

Nanette Hayes: jazz-playing saxophonist, in New York City, by Charlotte Carter

Lee Hayes: black police detective in New York City, by Ed Lacy

Tamara Hayle: black ex-cop turned private investigator in Newark, New Jersey, by Valerie Wilson Wesley

Sheridan Haynes: Sherlock Holmes actor in England, by Julian Symons

Amanda Hazard: sexy small-town CPA, in Vamoose, Oklahoma, by Connie Feddersen

James Hazell: tough private investigator in the East End of London, England, by P.B. Yuill

Cheney Hazzard: private security agent in Brownsville, Texas, by R.D. Brown

Inspector Hazelrigg: British police inspector in London, England, by Michael Gilbert

Patrik Hedstrom: police detective, and Erica Falck, a writer, in the fishing town of Fjällbacka, Sweden, by Camilla Läckberg 

Gerry Heffernan: Detective Inspector, and Wesley Peterson, a detective sergeant, in South Devon, England, by Kate Ellis

Merton Heimrich: lieutenant for the New York State Police Bureau of Criminal Identification, in The Corners, Putnam County, New York, by Richard Lockridge

Ben Helm: ex-cop turned private investigator in New York City, by Bruno Fischer

Helen Hewitt: female governor of an all-male high security prison, by Lynda La Plante 

Martin Hewitt: solicitor’s clerk in turn-of-the-19th-century London, England, by Arthur Morrison

Lieutenant Hilderbrand: homicide detective in Houston, Texas, by J.W. Kerr

Abbess Helewise and Sir Josse d’Acquin, a French knight, at the Hawkenly Abbey in England during the 12th century, by Alys Clare

Nate Heller: 1930s ex-cop turned private eye, in Chicago, Illinois, by Max Allen Collins

Nick Heller: ex-Special Forces, now an international security consultant, by Joseph Finder

Jonathan Hemlock: art professor and US government hit man by Trevanian

Dixie Hemingway: former sheriff’s deputy, now a professional pet sitter in Sarasota, Florida, by Blaize Clement

Edwina “Eddie” Henderson: officer in the Royal Canadian Mounted Police, in Sechelt, British Columbia, Canada, by L.R. Wright

George Hennessey: chief inspector, and Detective Sergeant Yellich, with the Vale of York police, in England, by Peter Turnbull

Rachel Hennings: bookstore owner in Los Angeles, California, by Jon Breen

James “Professor Puff” Henry: divorced librarian in the Shenandoah Valley, Virginia, in the Supper Club mysteries by J.B. Stanley

Kate Henry: baseball sportswriter in Toronto, Canada, by Alison Gordon

Susan Henshaw: suburban housewife sleuth in Connecticut, by Valerie Wolzien

Nick Herald: professional genealogist in New Orleans, Louisiana, by Jimmy Fox

Timothy Herring: running a society for Preservation of Buildings of Historic Interest, in London, England, by Malcolm Torrie (Gladys Mitchell)

Claudia Hershey: police detective in Florida, by Laura Belgrave

Tom Hickey: private investigator, in California and Nevada, and the next generation, Clifford Hickey, by Ken Kuhlken

Brett Higgins: lesbian sleuth with a criminal past, in Detroit, Michigan, by Therese Szymanski

Karen Hightower: (aka Bast), a white witch and graphic designer in New York City, by Rosemary Edghill

Katya Hijazi: a forensic scientist, and Nayir Sharqi, a Palestinian-Bedouin desert guide, in Jeddah, Saudi Arabia, by Zoë Ferraris

Dr. Tony Hill: criminal profiler, by Val McDermid

Inspector Judy Hill and Chief Inspector Lloyd, cops and lovers in East Anglia, England, by Jill McGown

Nicolette (Nikki) Hill: 30-something black prosecutor in Los Angeles, California by Dick Lochte and Christopher Darden

Jake Hines: police detective in fictional Rutherford, Minnesota, by Elizabeth Gunn

Willa Hinshaw: spunky associate minister at Liverpoole First United Methodist Church, in Liverpoole, North Carolina, by Lynette Hampton

Holly-Jean Ho: bisexual Anglo-Chinese computer fraud consultant and private investigator, in London, England, by Irene Lin-Chandler

Stewart “Hoagy” Hoag: celebrity ghostwriter in the United States, and his faithful basset hound, Lulu, by David Handler

Bartholemew Hoare: British Navy officer wounded in the throat during the Napoleanic Wars of the early 1800s, and assigned to espionage duties, by Wilder Perkins

Nick Hoffman: gay professor in Michiganapolis, Michigan, by Lev Raphael

Nikolai Hoffner: police detective starting in 1919, continuing into the Weimar period in Berlin, Germany, by Jonathan Rabb

Sidney Holden: hit-man, in New York City, by Jerome Charyn

Vicky Holden: Arapaho attorney, and John Aloysius O’Malley, a Jesuit missionary, on the Wind River Reservation, Wyoming, by Margaret Coel

Tom Holder: overweight 40-something police chief, and Reverend Kathryn Koerney, in the affluent university town of Harton, New Jersey, by Cristina Sumners

Harry Hole: police detective in Oslo, Norway, by Jo Nesbø

Billy Bob Holland: attorney and former Texas Ranger, in Deaf Smith, Texas, by James Lee Burke

Hack Holland: hard-drinking lawyer, Korean War POW, progressive Democrat, now a sheriff, in Texas, by James Lee Burke

Primrose Holland: ex-pathologist turned advice columnist, in Skipley, England, by Jo Bannister

M.J. Holliday: medium and ghostbuster, and her partner Gilley, in the Ghost Hunter mysteries by Victoria Laurie

Paula Holliday: 30-ish former TV executive who opens a landscaping-gardening business in Springfield, Connecticut, in the Dirty Business mysteries by Rosemary Harris

Grace Hollister: American schoolteacher and literary scholar visiting her favorite poets’ old haunts in England’s Lake District, in the Poetic Death mysterie by Diana Killian

Barbara Holloway: defense attorney in Oregon, by Kate Wilhelm

Patricia Anne “Mouse” Hollowell: retired English teacher, and Mary Alice “Sister” Crane, who out-lived three husbands, in Alabama, in the Southern Sisters mysteries, by Anne George

Dr. Kate Holly: clinical psychologist, by Charlotte Hughes

Rick Holman: private investigator, in Hollywood, California, by Carter Brown

Sherlock Holmes: detective in London, England (the original), by Arthur Conan Doyle

Sebastian Holmes: fathered out of wedlock by Sherlock Holmes while recuperating from his tumble off the Reichenbach Falls, by Brian Freemantle

Sherlock Holmes: detective in London, England, by Rick Boyer

Sherlock Holmes: detective in London, England, by Carole Bugge

Sherlock Holmes: detective in London, England, by Philip J. Carraher

Sherlock Holmes: 19th century consulting detective in London, England, by Loren D. Estleman

Mycroft Holmes: Sherlock’s older brother, in London, England, by Quinn Fawcett

Schlock Homes of 211B Bagel Street, a Sherlockian pastiche with a Yiddish perspective, in London, England, by Robert L. Fish

Sherlock Holmes: pastiches by H. Paul Jeffers

Sherlock Holmes and Mary Russell, his student and then wife, by Laurie R. King

Sherlock Holmes, from the posthumous memoirs of Dr. Watson, in the 1890s in Europe, by Nicholas Meyer

Sherlock Holmes: British detective, and Shadwell Rafferty, an Irish saloonkeeper in Minnesota, by Larry Millett

Sherlock Holmes pastiches by Barrie Roberts

Sherlock Holmes: detective in London, England, from the journals of Dr. Watson, by Wayne Worcester

Mrs. Hudson: housekeeper for the other sleuth of Baker Street, in London, England, by Sydney Hosier

Nick Holroyd: detective inspector in Dorset, England, by Ann Quinton

Max Holt: young genius and animal rights activist, and Jamie Swift, an editor of a newspaper, in Beaumont, South Carolina, by Janet Evanovich with Charlotte Hughes

Samantha Holt: veterinary technician in Paradise Cay, Florida, by Karen Ann Wilson

Reverend Lucas Holt: Episcopal priest and ex-prison chaplain, in Austin, Texas, by Charles Meyer

Julia Homburg: leading actress with the Burg Theater in the late 1930s and 1940s, in Vienna, Austria, by Sarah Gainham

Charles Honeybath: portrait painter in London, England, by Michael Innes

Chris Honeysett: artist and private investigator, in and around Bath, England, by Peter Helton

Charles Hood: sheriff’s deputy in Los Angeles County, California, by T. Jefferson Parker

Detective Sergeant Bert Hook and Superintendent John Lambert, policemen and golf enthusiasts in Gloucestershire, England, by J.M. Gregson

Alison Hope: software designer, and Nick Trevellyan, a detective inspector, in Hop Valley, England, by Susan B. Kelly

Matthew Hope: attorney in Florida, by Ed McBain

Lloyd Hopkins: detective sergeant in the Rampart Division in Los Angeles, California, by James Ellroy

Marty Hopkins: deputy sheriff in Nichols County, Indiana, by P.M. Carlson

Ward Hopkins: former CIA agent, and Nina Baynam, a former FBI agent, who continually cross paths with a serial-killer cult, by Michael Marshall

Turing Hopper: Artificial Intelligence Personality (AIP) in Crystal City, outside Washington, DC, by Donna Andrews

Evan Horne: jazz piano player with an injured hand, by Bill Moody

Andy Horton: detective inspector, and his sidekick sergeant Barney Cantelli, in Portsmouth, England, in the Marine mysteries by Pauline Rowson

Harry Houdini: escape artist, by Daniel Stashower

Duffy House: ex-sportswriter turned investigator in Chicago, Illinois, by Crabbe Evers

Carl Houseman: deputy sheriff in Iowa, by Donald Harstad

Charlie Howard: mystery writer and professional thief, in Europe, by Chris Ewan

Jeri Howard: private investigator in Oakland, California, by Janet Dawson

Sharyn Howard: sheriff in Diamond Springs, North Carolina, by Joyce and Jim Lavene

Emma Howe: 50-something owner of a private detective agency, and Billie August, a young single mother, in Tiburon (Marin County), California, by Gillian Roberts

Nicholas Howard: manuscript dealer in England, by George Sims

Tamara Hoyland: British secret agent and archaeologist, in England, by Jessica Mann

T.S. Hubbert: retired personnel director, and 84-year old Auntie Lil, retired from the garment industry, in New York City, in the Partners in Crime series by Gallagher Gray (Katy Munger)

Honey Huckleberry: book rep based in Fort Worth, Texas, by Margaret Moseley

Mrs. Hudson: housekeeper for the other sleuth of Baker Street, in London, England, by Sydney Hosier

Robin Hudson: cable news reporter in New York City, by Sparkle Hayter

John Hugo: police lieutenant in Florida, by Alan Green

Liu Hulan: Chinese police inspector, and David Stark, an American attorney, combining talents to solve mysteries in China, by Lisa See

Pippa Hunnechurch: owner of her own executive recruiting firm in Ryde, Maryland, by Ron Benrey & Janet Benrey

Elsie Mae Hunt and Tim Mulligan, professional archeologists and amateur sleuths, by Aaron Marc Stein

Gil Hunt, bookstore owner and Claire Hunt, a local celebrity in St. Louis, Missouri, by Robert J. Randisi with Christine Matthews

Lorraine Hunt: detective inspector in Houghton-le-Spring, northeast England, by Sheila Quigley

Morgan Hunt: Vietnam vet, ex-con, private investigator working for a crusading lawyer, in Pensacola, Florida, by Geoffrey Norman

Chad Hunter and Frank Baldwin, weapons experts, in the Hypershot thrillers, by Trevor Scott

Dr. David Hunter: forensic anthropologist in England, by Simon Beckett

Ed Hunter: young Chicago teenager, and his uncle Ambrose Hunter, a carny worker, by Fredric Brown

Leah Hunter: 25-year-old tax inspector, in England, by Sarah Lacey (Kay Mitchell)

Philip Hunter: detective superintendent, in fictional Yoreborough (York), England, by Maurice Procter

Robert Lee Hunter: wealthy 30-something private investigator, in New Jersey, by Eric Sauter

Sam Hunter: crude private investigator, in Los Angeles, California, by L.A. Morse

Irene Huss: detective inspector in the Violent Crimes Unit in Goteborg, Sweden, by Helene Tursten

Kek Huuygens: Polish smuggler using a Dutch name and an American passport, in Europe, by Robert L. Fish

Huy the Scribe, during the time of Akhenaten and Tutankhamun in the 18th Dynasty around 1350 BCE, in ancient Egypt, by Anton Gill

Lexy Hyatt: lesbian crime reporter in Florida, by Carlene Miller