Another Time, Another Place (S01E16)

After the moon emerges from a space warp, Moonbase Alpha operative Regina Kesslann suffers delusions that she is married to Eagle pilot Alan Carter, that he and Commander Koenig are dead and that she's living on a planet. The rest of the crew are initially delighted when they find that the moon is back in the solar system, but their joy is short-lived - there's another moon in Earth's orbit and they are heading straight for it. And there's even a carbon copy of Moonbase Alpha, one where Koenig and Carter were killed in an Eagle accident. (iTunes)