For many years Mayhew's life after playing for Genesis was a mystery to most fans. It was said that his "Trespass" royaltycheque had gone unclaimed. There were rumors that he was dead or missing. In 1979, he moved to Australia. He eventually found work as a carpenter. He is now an Australian citizen. In 2006, Mayhew attended the Genesis Convention in London along with Anthony Phillips and Steve Hackett. He even played drums for a tribute band's performance of "The Knife" (from "Trespass"). He died a day before his birthday from a heart attack.