After Spencer derails, Rudolph Diesel sells the Duke and Duchess a new diesel engine to replace Spencer. Upon his arrival, the Duke and Duchess sell their old private engine, Spencer, to Sir Topham Hatt.
On his maiden voyage, the diesel overheats. Subsuquently, he is sold back to Rudolph Diesel and sent to the Dieselworks to be repaired.
James was suppose to deliver Derek's new parts, but accidentlly lost the truck through the Skarloey Railway tunnel, leaving the green diesel stuck at The Sodor Dieselworks with only Den for company.
Eventually Derek does start to worry for his new parts as they were suppose to be delivered some time ago, Den agrees with him, and decides that the two should go to sleep. However later that night, Derek is awoken to some strange noises, looking around he finds Simon and some members from the Blockade Committee, Derek asks them what they were doing, but doesn't get an answer as Simon then sets the Dieselworks ablaze.
The next morning as a tramatized Den emgerges from the Dieselworks covered in black soot, the firemen tell Sir Topham Hatt that Derek had perished in the flames right before Simon pins the blame on Mr. Percival. It is unknown where Derek's remains are, but are most likely in the Diesel Statue at Maron Park
- Season 1: Modernization Marches On (not named), Revolutionary (not named), The Blockade Committee (mentioned, not named), Change, Conflict Resumes