 Geoff also alludes that there was a rumor circling about a lieutenant-commander having an affair with a student on a course he was teaching, a rumor he tells only to Mike and Kate.Though Geoff is soon arrested for his part in arms dealing, the incident leads both Mike and Kate to rethink their positions on having a relationship.Mike was promoted to Commander in the first episode of Season 4 (“Night of the Long Knives”), and left the "Hammersley" for a shore posting at NavCom, allowing him to explore his relationship with Kate.