The Phoenix Saga (2): The Dark Shroud - S3-E4
Continuity mistake: When Xavier is looking at Moira and Banshee from his window, as the camera zooms in on the latter two, you can see they are facing each other, and Moira has her left arm on or near Banshee's hip. When the shot changes, they are standing side by side, with Moira's arms wrapped around Banshee's left arm. (00:17:41)