Detective Comics, Vol. 1

The Challenge of Clay-Face -

The Man Who Impersonated J'onn J'onzz - A famous impersonator plans to make a comeback by impersonating the Martian Manhunter. He hurts his leg, so the real Manhunter performs his act using the props provided. When a real gang of crooks shows up, J'onzz has to bring them in without giving away the game.

The Secret Sentry Of the Sea - Aquaman provides security for diplomats who are signed a peace treaty at sea.