Amy's Valentine's Flowers (S02E03)

It’s Valentine’s Day, and various people have received anonymous cards and/or extravagantly large bunches of flowers. Naturally, suspicions run high in the Jessop household. Meanwhile, trainee police officer Paul has a brilliant plan to ingratiate himself with the CID lads. All he has to do is pretend to like football. And Robin’s gearing himself up to propose to Cherry, if he can come up with a suitably grand romantic gesture. (BBC iPlayer)