Baa! is the eighth episode ever made in Season 5.
Percy is taking some flowers to Maithwaite for a "best-dressed engine" competition. On the way, he is stopped by a ram on the tracks. His driver lures it away with some cabbage and at Maithwaite, the stationmaster tells them the ram has a reputation for always being hungry. Percy is later looking forward to a snooze when he hears a commotion at the station and goes to investigate. He discovers the decorations have been ruined and the ram, suspected to be the culprit, has taken three boys "hostage" in the waiting room. The boys beg to be let out if they apologize, and it is discovered they are the vandals. Everything is fixed, and Maithwaite is declared the winner. At the prize-giving ceremony, the Fat Controller gives the ram a pumpkin, but Harold accidentally blows his top-hat and the contented ram munches on it instead.
- Thomas has Edward's whistle sound.