On TPTV and I'd seen it a couple of times before, but it is such a classic and had so many great stars in it, I just had to watch it again.
Dodger Lane (Peter Sellers) and his two cell mates (Bernard Cribbins and David Lodge) plan to break out of prison to steal a load of diamonds (worth £2,000,000 THEN), then break back into prison after the job giving them the perfect alibi, which is all arranged by one of their old gang on the outside Soapy Stevens, played superbly by Wilfrid Hyde-White.
Lionel Jeffries as Chief P.O. Crout (as only he can play a vicious screw), Liz Frazer as Dodger's moll and Irene Handl as Bernard's mum, all make for an absolutely brilliant British comedy. Must mention Beryl Reid too, as a prison visitor - so funny.