Percy is a small green saddle tank who lives on the Island of Sodor
Percy was built in 1900 for a small foundry in Essex, it closed town in 1907 and Percy was sent back to his workshop. Later in 1926, The Fat Controller I bought Percy to help out when the big engines were on strike. When Duck arrived in the yard, Percy came to Thomas' Branch Line where he has worked ever since. He soon became friends with Thomas, although falling out with each other from time to time. In 2005, he Thomas and Toby triple headed along the Ulfstead Extension.
Percy is very mischievous, he likes to play jokes on the bigger engines. This often lands him in trouble, but never learns. However, he can be quite wise and independent during difficult situations; which Toby and Thomas are impressed by.