Derek is a diesel engine with bad "teething" troubles. He works at Anopha Quarry.
BoCo soon came to Derek's rescue.
Unfortunately, Derek soon overheated when he came to a hill he didn't expect. He soon stopped; leaving Bill and Ben having to pull the train and Derek at the same time.
Derek is a friendly diesel engine with bad teething troubles. He overheats every time he comes to a hill; he is often found working at Anopha Quarry with Bill and Ben.