Having received an invitation to a fancy dress party, Mr Benn sets off to find a costume to wear. However, all the shops he visits have only day-to-day clothes, and he is just about to give up when he turns down a small lane and finds a costume shop filled with strange outfits. After asking the shopkeeper if he can try on a suit of red armour, Mr Benn steps into the changing room, puts on the outfit and then walks through another door… and finds himself back in medieval England. Here Mr Benn meets a very sad dragon, who explains that he used to be King’s personal fire-lighter until a crooked match-seller framed him for setting fire to a few of the villagers’ barns. Mr Benn decides to help put things right for the dragon…
