Star Trek: The Animated Series

The Lorelei Signal (1x4)

Air date: Sep 29, 1973

Investigating a sector of space where starships have disappeared every 27 years, the U.S.S. Enterprise male crew are attracted by a mysterious signal. Kirk beams down with a landing party and encounters a race of beautiful women who survive by drawing the energy from the male members of the ships that they have lured to their planet.