The Wrong Case by James Crumley is the first in Crumley's Milo Milogovitch detective series. This novel finds Milo desperate for cases in his private detective firm after the change in state divorce laws. As Milo tries to decide how he might pay his bills that month, a woman walks into his office and asks Milo to find her brother. Milo sees the case as a dead end, but takes it because he needs the money and he is drawn to the woman. However, the case turns out to be much more complicated than even Milo could have imagined, dragging him into a drama that delves deep into the underbelly of the criminal world hidden in his beloved hometown. The Wrong Case is a detective novel that harkens back to the days of Hammett, leaving the readers begging for more.

Milo is watching a traffic accident outside his office window when Helen Duffy walks in. Helen is vulnerable, anxious to find some help but reluctant to share her story. Milo finally gets Helen to tell him about her brother, Raymond, a scholar who has suddenly gone missing. Milo decides to take the case not because he thinks he can help but because he is drawn to this beautiful, fragile woman.

Milo begins his investigation in his favorite bar, getting information on Raymond Duffy from a surprising source, his drinking buddy Simon. Milo finds some of Raymond's acquaintances, only to discover that Simon has beat him to the location. Milo tries to get information from Raymond's lover, Lawrence Reese, but finds Reese uncooperative. Milo ends up shooting the porch supports of Reese's house with a shotgun, bringing out the cops and Milo's old friend, Jamison. Milo is arrested.

The following day, Milo learns that Helen Duffy's brother has been found dead in a restroom of a local bar. The cause of death is a drug overdose, but Helen Duffy refuses to believe that her brother was a drug addict, let alone that he would kill himself. Helen returns to Meriwether and tells Milo a sob story, begging him to find out who murdered her brother. Milo agrees, once again because he is drawn to Helen Duffy.

Milo speaks to Raymond's ex-lover, a university professor, and learns nothing more than Raymond's fascination with guns and his tendency to violence. Milo also locates Reese on a farm a distance from Meriwether. Reese is still reluctant to speak to Milo, but finally tells him what little he knows about Raymond. What Reese has to say, however, supports the coroner's finding of a drug overdose. When Milo returns to town after visiting Reese, he learns that Simon has been found in Reese's former rent house and that the university professor is also dead.

As Milo continues to investigate Raymond Duffy, he is hired to follow a woman by Nickie DeGrumo, a local motel owner. Nickie appears nervous when he hires Milo and instructs Milo to drop all other cases. Milo agrees, taking Nickie's money, but continues to investigate Raymond anyway while he assigns a fellow drunk to Nickie's case. A short time later, Milo is jumped in the streets where he is forced to kill a man.

Milo has a breakdown and goes on a day's long drunk. When he recovers, Milo again interviews people about Raymond. When Milo speaks to the bar owner where Raymond was found dead, he makes a connection to Nickie. Milo confronts Nickie, causing Nickie to have a fatal heart attack. Members of Mama D's family try to convinces Milo to hide Nickie's connection to the drugs that Raymond was selling and using, but Milo fights back, leaving both men dead.

Back at home, where Helen has been living with him since his long drunk, Milo finds Helen's mother. Helen's mother informs Milo that Helen is a compulsive liar. Not only this, but Helen was Raymond's biological mother. Helen leaves with her mother, leaving Milo heartbroken. However, Milo turns to the bottle and forgives Helen.