While scuba diving in Cardiff Bay, he, Anthony Bee and Sandra Applegate found and entered a Bruydac ship. The only survivor inside was able to overpower them. He implanted them each with control devices, then let them out to find something to repair his ship.
Guy was able to use his connections with Blaidd Drwg to steal six uranium cores.
He killed a Big Issue vendor on Gwion Lane, Splott. He later signed out of work ill, and was driven home along the M4 to Butetown by his secretary, Jennifer Fallon. He digested her, stole her coat and fled the scene. Jack Harkness and Gwen Cooper caught up with Guy in the Hayes district of Cardiff. They pursued him along Blackfriar Way to a construction site. There, he intentionally fell to his death from the eighth floor of the development, into the path of a bus.
Owen Harper's autopsy on Wildman's body revealed that he had osseus tissue in his upper gastrointestinal tract, but nothing beyond the pyloric antrum. His face was an unrecognisable pulp and his ribs had been smashed upon impact. His large intestine had been lacerated by a penetrating injury upon landing. He had non-human elements in his oesophagus, stomach, pancreas, duodenum and spleen and an alien device inserted into his spine. Ultimately, his death was caused by a depressed skull fracture and cerebral bleeding.
He was around five foot six and broad. He had grey hair. His autopsy suggested that he was a non-smoker who "enjoyed a drink", with no indication of drug use, prescription medicines or poisons. (PROSE: Another Life)