The Outer Limits 1963 S2 E2 Cold Hands ,Warm Heart

After completing the first crewed mission to orbit Venus, astronaut Jeff Barton returns to Earth with recurring nightmares and an increasing inability to stay warm. Barton's condition continues to worsen and is accompanied by a peculiar webbing of his fingers. Only after his nightmares become more vivid does he recall an unrevealed alien encounter in the Venusian atmosphere. Barton's doctors suspect the astronaut had been genetically affected by his mission, and they then struggle to treat and cure him before his mutations completely take over.