What would you do if you thought your hamster only had a week to live, your chickens are attacking you with machine guns, and your Nan is just not giving you the space to spread your wings? When Harry and his Nan (Julie Walters) discover their hamster is seriously ill they set off on a road trip to Blackpool pursued by a lunatic vet (Simon Bird). Along the way, Harry falls in love with an undersea shell person (Sheridan Smith), witnesses canine superstars The Dachshund Five, and meets indie rock band The Magic Numbers - who run a B'n'B. It all culminates in a fight on top of The Blackpool Tower. Who could be behind it all? Could it be Harry's evil twin Otto (Matt Lucas), who was separated from Harry at birth and brought up by Alsatians?