Writer	Who	Where	When	How Much	Why
O'Boyle, Cherie	Estella Nogales	Arroyo Loco, CA	present		Very enjoyable--especially the witty (and, sadly, somewhat accurate in real life) descriptions of neighbors in a homeowner's association. The reason I rated it 5 instead of 6 is that Estella doesn't do very much investigation--only talks to neighbors.
O'Connor, Carlene	Siobhan O'Sullivan	Kilbane, Ireland	Present		Siobhan O'Sullivan is newly-trained garda stationed in her hometown of Kilbane. The local priest comes to Siobhan's door late at night to tell her about finding a dead man--above ground--in the local cemetary. To discover the man's identity and "who dunnit", Siobhan must deal with politics at the garda station and even more complicated, she must work with her ex-boyfriend, Macdara.
O'Connor, Carlene	Cormac O'Brian--garda, Dr. Dimpna Wilde--veterinarian, Sergeant Barbara Neely--garda	Dingle, Ireland	Present
Odden, Karen	Nell Haddam	London, England	1875		Nell, who lives with her brother, Matthew, a Scotland Yard detective, takes a job--pretending to be a boy--as a pianist at the Octavian Theater to earn money to pay her tuition--if she passes the Royal Academy of Music's audition. The Octavian's owner, Drummond, is not very likable, but Nell becomes more and more attached to Drummond's son, Jack, who is not like his father. Matthew tells Nell he is investigating a hugh thieving ring, and Nell discovers Drummond is part of the thieving ring. Nell and Jack help Drummond get out of England just before the police raid the Octavian, and they help the police stop a hugh heist.
O'Donnell, Lillian	Nora Mulcahaney	New York, NY	Present
O'Donnell, Paraic	Inspector Cutter, Scotland Yard, Gideon Bliss, student at Cambridge, and Octavia Hillingdon, ward of newspaper publisher and young journalist	London and Kent, UK	1893		Gideon receives a letter from his uncle asking him to return to London immediately, but when Gideon arrives, his uncle has disappeared. Gideon works with Inspector Cutter and Octavia Hillingdon to find his uncle. They discover that two noblemen have been capturing women with a certain "soul brightness", killing the women, and trying to absorb the "soul brightness" as the women die in an attempt at rejuvenating themselves. They discover that Gideon's uncle has been trying to protect some women from these men.
O'Kane, Leslie	Allie Babcock	Berthoud and Boulder, CO	Present		Allie is pet therapist
O'Marie, Sister Carol Anne	Sister Mary Helen	San Francisco, CA	Present		Sister Helen lives in convent on Turk Street
O'Shaughnessey, Perri	Nina Reilly	Lake Tahoe, CA	Present		Nina is attorney
Offord, Lenore Glen		San Francisco, CA	1940s
Oleksiw, Susan	Joe Silva	Mellingham, MA	Present
Oliphant, B. J.	Shirley McClintock	Colorado and New Mexico	Present
Oliver, Steve	Scott Moody	Spokane, WA	Present		Scott drives a cab and suffers from schizophrenia
Olson, Karen E.	Annie Seymour	New Haven, CT	Present		Annie is crime reporter
Orczy, Baroness Emma	Polly Burtin	London, England	early 1900s		Polly is reporter for the Evening Observer, and a man who sits at the corner table of the lunchroom tells Polly solutions to mysteries that are baffling the police.
Orde, A. J.	Jason Lynx and Grace	Denver, CO	Present		Jason is antiques dealer
Orgain, Diana	Kate Connolly	San Francisco, CA	Present		Kate's friend, Paula, is an interior decorator, who has been hired to redecorate one of San Francisco's "painted ladies". The house belongs to Glenn and Carry, aand they have a tenant renting the house. Since Glenn and Carry want to move into the house, they are trying to buy out the rest of the tenant's lease. When Paula and Glenn go to view they house, Kate tags along. Inside a closet they find Carry's body--she has been strangled. Due to some flirtatious texts from Glenn to Paula, the police assume Paula wanted Glenn to herself and strangled Carry. Kate discovers who really dunnit and rescues Paula. Light but very readable
Osborne, Denise	Salome Waterhouse	Santa Cruz, CA	Present		Salome is Feng Shui consultant
Osler, Rob	Harriet Marlowe	Chicago, IL	1898		Harriet applies to the Prescott Detective Agency, and she is--provisionally--hired as an operative. Her first assignment is to find Mr. Prescott's neighbor's missing maid, Agnes Woziak, and Harriet is given one week to complete the assignment. Harriet does find Agnes within the deadline and is given a permanent job. A little slow at getting into the plot, but a super plot twist before ending.
Osman, Richard	Elizabeth, Joyce, Ibrahim, and Ron (residents of Coopers Chase Retirement Village and members of the Thursday Murder Club), PC Donna de Freitas, and PC Chris Hudson	Fairhaven, Kent, UK	Present		Outstandly readable, some parts very funny, but, ultimately, plot much too sad
Overholt, Cuyler	Gemevieve Summerfield, M.D.	New York, NY	1907		Genevieve trained as a M.D. and has also studied psychiatry; she now works in a women's clinic, and one of her patients is accused of murder
Outland, Orland	Doan McChandler and Binkey	San Francisco, CA	Present		Doan is drag queen