McDermid's notable characters are a lesbian journalist, Lindsay Gordon; a private investigator, Kate Brannigan; and a psychologist, Tony Hill, who suffers from sexual dysfunction. Her books mainly fall into three series: Lindsay Gordon, Kate Brannigan, and, beginning in 1997, the Tony Hill and Carol Jordan series, the first entry in which, The Mermaids Singing, won the Crime Writers' Association Gold Dagger for Best Crime Novel of the Year. The Hill/Jordan series has been adapted for television under the name Wire in the Blood, starring Robson Green.
McDermid considers her work to be Tartan Noir. As well as her novels, McDermid contributes to several British newspapers and often broadcasts on BBC Radio 4 and BBC Radio Scotland.