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

Hagen: government agent in the USA, by Kay Hooper

Richard Hagen: diamond dealer in 1940s Antwerp, Belgium, by J. Robert Janes

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

HLeo 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

Max Hale: reluctant detective, by George Harmon Coxe

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

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

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

Em Hansen: forensic geologist in Wyoming, by Sarah Andrews

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

Dick Hardesty: a gay detective, by Dorien Grey

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

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

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

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

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

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

Harpur, Colin: detective chief superintendent in an English seaport by Bill James

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

Harris, Leah: Seattle Police Detective Sergeant in Seattle Washington by Michael A. Hawley

Harris, Paul: a Scot with a heavy equipment business in Singapore by Gavin Black

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

Chip Harrison by Lawrence Block

Hartley, Beth: an attorney turned legal researcher 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

Haskell, Ben: writer/chef  in Chitterton Falls, England by Dorothy Cannell

Haskell, Ellen: interior decorator in Chitterton Falls, England by Dorothy Cannell

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

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

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

Hastings, Stanley: married actor and private eye in New York, New York by Parnell Hall

Hatch, Jake: railroad detective in the United States by Robert Campbell

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

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

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

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)

Hawkin, Alonzo: homicide detective in San Francisco, California by Laurie R. King

Hawks, Joaquin: a CIA operative by Bill S. Ballinger

Hawley, Bill: an undertaker by Leo Axler

Hawthorne, Connor: a 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

Haycastle, Matilda: a temporary in Brussels, Belgium by Michele Bailey

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

Hayes, Cinda: an 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

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

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

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

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

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

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

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

Heffernan, Gerry: his boss in South Devon, England by Kate Ellis

Heimrich, Merton: lieutenant for the New York State Police Bureau of Criminal Identification by Richard Lockridge

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

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

Hewitt, Martin: a solicitor's clerk  in turn-of-the-century London, England by Arthur Morrison

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

Helewise, Abbess: an abbess at the Hawkenly Abbey in England, during the 12th century by Alys Clare

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

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

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

Hemingway, Ernest: expatriate writer in Paris in the 20's by Walter Satterthwait

Henderson, Edwina “Eddie”: woman officer in the Royal Canadian Mounted Police, in Sechelt, British Columbia, Canada, in the continuation of the Karl Alberg series by L.R. Wright

Hennessey, George: chief inspector with the North Yorkshire Police in England by Peter Turnbull

Hennings, Rachel: a 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

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

Henshaw, Susan: Connecticut suburban housewife sleuth by Valerie Wolzien

Herald, Nick: a 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)

Hershey, Claudia: a police detective in Florida by Laura Belgrave

Hickey, Tom: private investigator during the 1940s and 1950s in California and Nevada by Ken Kuhlken

Higgins, Brett: in Detroit, Michigan by Therese Szymanski

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

Hill, Dr.: a profiler by Val McDermid

Hill, Darby: a communication expert in Oakland, California by Louise M. Hoblitt

Hill, Inspector Judy: a cop in East Anglia, England by Jill McGown

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

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

Hinshaw, Willa: a 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

Hoag, Stewart “Hoagy”: celebrity ghostwriter in the United State 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

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

Holcomb, Lenny: an obituary writer in Harrisburg, Pennsylvania by John Luciew

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

Holden, Vicky: an Arapaho attorney in Wind River Reservation, Wyoming by Margaret Coel

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

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

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

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

Holloway, Barbara: Oregon defense attorney by Kate Wilhelm

Hollowell, Patricia Anne: “Mouse”: housewife and sister in Alabama by Anne George

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

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

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

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

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

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

Holt, Max: a young genius, animal rights activist in Beaumont, South Carolina by Janet Evanovich with Charlotte Hughes

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

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

Homes, Schlock: a satire of Sherlock Holmes in London, England by Robert L. Fish

Hook, Detective Sergeant Bert: a policeman and golf enthusiast in Oxford, England by J. M. Gregson

Hope, Alison: software designer in Hop Valley, England by Susan B. Kelly

Hope, Matthew: attorney in Florida by Ed McBain

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

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

Hopkins, Ward: a former CIA agent who continually crosses paths with a serial-killer cult by Michael Marshall

Hopper, Turing: an Artificial Intelligence Personality (AIP) is Crystal City, outside Washington D.C. by Donna Andrews

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

Houdini, 19th century escape artist in London, England by Walter Satterthwait

Houdini, Harry: an escape artist by Daniel Stashower

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

Houseman, Carl: deputy sheriff in Iowa by Donald Harstad

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

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

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

Hubbert, Theodore: a retired  Wall Street executive in New York, New York by Gallagher Gray 

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

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

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

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

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

Hunt, Claire: local celebrity in St. Louis, Missouri by Robert J. Randisi

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

Hunt, Gil: bookstore owner in St. Louis, Missouri by Robert J. Randisi

Hunter, Ambrose: Ed’s uncle and carny worker in Chicago, Illinois by Fredric Brown

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

Hunter, Diana: a private eye in Southern California by Joan Francis

Hunter, Ed: a young teenager in Chicago, Illinois 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

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

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

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