Percy is a small, cheeky little saddletank. Percy is incredibly accident-prone, and has had the most accidents. He used to have a small rivalry with Harold but they are now good friends. He also had held a grudge from the big engines about their tricking him into misinterpreting a signal, but silenced this with some help from Duck. This shows that, when nonsense goes too far, Percy will not stand for it and seek help to settle the matter for good, even if he faces reprimanding from Sir Topham Hatt for doing it. Now, Percy mostly gets along with some of the bigger engines.