Billy is an orange tank engine with prominent buck teeth.
When Billy first arrived on the railway, Thomas was asked by Sir Topham Hatt to show Billy around. But Billy misconstrued Thomas' advice for bossiness and so refused to listen to him, causing Billy to fail to complete his deliveries. At last, Thomas lost patience and told Billy to do his own thing. Billy was delighted, but his happiness was short-lived as he swiftly ran out of coal and water. In future, Billy paid attention to advice, worked hard with every job he did and was happy that Thomas helped him as his new friend.
Billy is a bright orange tank engine who can be impetuous, impatient, and impulsive. Although he is bubbling with enthusiasm and keen to get stuck in, he tends to act before he thinks things through fully and can even end up keen to start one job before properly finishing another. He can be inattentive, does not always like being told what to do, and may try to work independently when, perhaps, he best not. He is often boisterous, has tendencies to be overconfident in his abilities, thinking he need not listen to advice from more experienced engines. Nevertheless, his enthusiasm is well-meaning and, when he keeps calm, thinks things through, pays attention, and follows instructions carefully, Billy can properly harness his energy and focus on what he is doing so that he can be a Really Useful Engine. If he ever gets snappy, his infectious get-up-and-go and burning desire to be useful will shine through and make it hard for any engine to really stay upset with him for very long.
Billy is based on a Manning Wardle L Class 0-6-0ST. Charlie is another member of this class.
Billy is painted orange with green and yellow lining. He has black nameplates with his name in gold on each side of his saddle tank.