Mannix is hired to vet a prospective bridegroom.

Mannix checks out an actress with an enemy.

The strong friendship between Lew Wickersham and Mannix melts into a violent and deathly feud. The bitter battle begins when Mannix launches an investigation into the theft of a highly secret formula for the development of a laser ray. Stolen plans and sabotage involve Intertect and their agents.

The two paths of the case meet at the water's edge.