He-Man and the Masters of the Universe (1983)

S2E1 The Shadow of Skeletor

After Beast Man crash-lands near Palace Eternia in one of Skeletor's shuttles, Adam, Teela, Man-At-Arms, Man-E-Faces, and Ram Man learn that he was destined for the Dark Moon of Eternia. Intrigued by Skeletor's intentions, they lock Beast Man away and decide to investigate the Dark Moon themselves. Upon arriving at Eternia's Bright Moon, they find that a conflict has erupted between the two moons, sparked by reports of Bright Moon inhabitants wreaking havoc on the Dark Moon. Realizing that Skeletor is behind the chaos, Man-E-Faces dons a Beast Man disguise to infiltrate the Dark Moon and uncover Skeletor's plot.