Stanley is a small, silver steamengine from Thomas & Friends. He only appeared in one DUPLOThomas & Friends set.
Stanley was brought to Sodor to take care of Thomas' workload during the restoration of Great Waterton. Upon his arrival, Stanley became very popular and enjoyed the company of the engines.
Stanley's popularity caused Thomas to feel jealous and later neglected. Thomas felt that Stanley was newer, bigger, and stronger than him - and would take over his place on the railway. Thomas then planned to make Stanley look weak - the trick backfired and caused Thomas' friends to consider him mean and incompetent.