Farscape - Season 2 Episode 10 -

An energy ball enters Moya, and comes into contact with everyone on board. When it reaches Crichton, it engulfs him, then a cave man comes out, followed by Crichton. Blood tests show the cave man is Crichton. Another Crichton emerges from the energy ball, this one is extremely advanced. The probe says it needs to study at least one of the Crichtons. If it doesn't get at least one of them back, it will destroy Moya.