When Tilly manages to make Hector's poorly knee better, she decides she is going to be Doctor Tilly. There is a special doctor's coat in the dressing up box and Tilly sets up her surgery immediately. But Tilly is a bit too enthusiastic at diagnosing her friends and starts administering medical help even when it's not wanted. The friends must try and explain to Tilly that part of being a good doctor is being able to listen!
