Fenton was a vampire's familiar captured by Sir Malcolm Murray and his associates. Vanessa Ives' latest vision led the group to the London Zoo. Hoping to find Mina, they instead encountered a rabid young man devouring flesh. Rather then kill him, Malcolm and the others brought the creature with them. It was decided that they would attempt to restore Fenton back to a normal human state and, in the process, perhaps learn Mina's whereabouts.
When Malcolm and the others found Fenton instead of Mina at the London Zoo, they decided to take him with them and question him concerning Mina. In Sir Malcolm's basement however, Fenton proved unwilling to help, but did confirm that his master wanted Vanessa. Sir Malcolm, Sembene and Vanessa considered using torture to get the answers they sought, but Ethan baulked at the idea of harming a child for whatever reason. Doctor Frankenstein arrived just in time, and suggested using blood transfusions to restore Fenton's humanity.
Back at Sir Malcom's, Victor went ahead with the blood transfusions, but was forced to use Malcolm's blood as Ethan refused to participate. Fenton reacted aversely to the treatment, so Victor and the others went upstairs to ponder their next move. They launched into another heated row about Fenton's treatment and failed to notice his escape. When strange noises were heard coming from Vanessa's room, Malcolm went to investigate. There he was confronted not only by Fenton but by the boy's master as well. Fenton was killed in the ensuing fight after he stumbled backwards and fell onto a shard of broken glass.
Some days later, Victor performed an autopsy on Fenton, but found nothing suspicious, and was puzzled at how the the boy was able to call for his master.