Lured by a gigolo, wealthy women studying ballroom dancing are blackmailed for all they're worth as Dancing in the Dark on Charlie's Angels. The lonely widow of a Baseball Hall of Famer is blackmailed after a short affair with a gigolo she met at her dance classes; Charlie's Angels are called in to investigate. Jill masquerades as a disco-dance instructor, Sabrina as a rich but socially inept heiress and Kelly as a replacement photographer, supposedly sent by the blackmailer's shutterbug. When Sabrina succumbs to the gigolo's charms, Kelly photographs; Bosley even shows up as the irate but blackmailed father. All goes well until the real photographer returns unexpectedly and exposes them all!