Thomas the Tank Engine is an anthropomorphised fictional tank locomotive in the British Railway Series books by Wilbert Awdry and his son, Christopher, published from 1945. He became the most popular and famous character in the series, and is the titular protagonist in the accompanying television adaptation series Thomas & Friends and its reboot Thomas & Friends: All Engines Go.

James the Red Engine is a fictional anthropomorphic red tender locomotive from The Railway Series children's books by the Reverend Awdry and the TV series adaptation Thomas & Friends. He has a 2-6-0 ("Mogul") wheel arrangement and is engine number 5 on the North Western Railway, the Fat Controller's railway on the Island of Sodor.