Byker Grove
Episode 177 (11x1)
:
When the kids notice Geoff being stand-offish they decide that he must be going through a mid-life crisis. In order to cheer him up they all get together to throw him a surprise 70's party.
It came complete with 'performances' by Charlie's Angels (and 'Charlie' who got a face full of cream) and the band The Who.
And on a less than cheery note Harry finally decides she's had enough of Ben and they break up.