It was written by Ben Elton, Rik Mayall, and Lise Mayer, and directed by Paul Jackson and Ed Bye.
The first shot knocks out Neil as he enters the room; the second involves Vyvyan not releasing the ball and running straight for Rick, clouting him on the head.
The four later receive their exam results from the postman, who has already read the letters and tells Rick that he "came bottom in the whole world", followed by Vyvyan, Mike, and Neil coming top out of the four.
They mess up their own robbery, but unwittingly take the proceeds from a separate ongoing one, and escape to Vyvyan's car, which he had parked in front of a lamppost.
With the police sirens in the distance, Rick leaves to find a new getaway vehicle, and returns with an AEC Routemaster double-decker bus, which they drive away to freedom.
[2] As the series comes to an end, the bus lands at the bottom of a quarry, and there is a pause until the lads remark: "Phew, that was close!
No explanation is given for how he survived being locked in Mike's room with man eating lions or reverted from being a homicidal axe-wielding maniac.