|Series 3, Episode 2|
|Air date||24 April 2006|
|Written by||John Johnson & J.C.Wilsher|
|Directed by||Rob Evans|
With the recent release of Cabinet papers under the 30-year rule, Jack pushes to reopen the investigation into the death of Joe Walsh, a left-wing union leader. His body was fished out of the Thames in the mid-1970s and his death put down to suicide, but it was clear that the Cabinet wanted his antics stopped, and Jack wonders if someone might have taken those wishes a little too seriously. There were rumours that Walsh had fiddled the union books, and several of his contemporaries are convinced he was disposed of by MI5. If that wasn't enough for UCOS to handle, Brian stops taking his medication, and his reckless actions threaten to have severe consequences for the rest of the UCOS team and jeopardies their chance of cracking the case.