Ex-convict Elrod Davis looks up fellow ex-con Gary Baker to become the "driver" in a bank robbery. Serpico joins the hold-up team and convinces Baker, who is married, to drop out. Before Baker leaves he betrays Serpico.

Several attempts to break a drug ring headed by "The Indian" fail. Serpico intentionally tips off The Indian's go-between Grace to an upcoming raid. He gets suspended but gains The Indian's trust. Serpico wants to meet and personally bust The Indian. Serpico reunites drug courier Heather with her father, and he has romantic interest in the hospital doctor caring for Heather.