Derek Warner was a friend of Tom Merrick. Derek was first seen in the Woolpack where he berated Amos Brearly saying how Tom always said he was stuck up. In 1980, Derek and Tom stole some Christmas trees from the NY Estates plantation, running Joe Sugden over in the process. They are both caught, and Derek and Tom were both given suspended sentences. In March 1984, a few years later Derek was in trouble again for poaching. In 1986, he murdered Harry Mowlam and held Donald Hinton hostage before being arrested.