He made his solo Edinburgh debut in 2005 with a show called 1984, describing the misery of growing up in the fictional Welsh town of Llanbobl, whihc was nominated for the Perrier best newcomer award. That year, he also won the Chortle award for best breakthrough act.
His 2008 Edinburgh show again caught the attention of judges and was nominated for the main if.comedy award. It lead to appearances on BBC One's Live at the Apollo stand-up showcase and the 80th Royal Variety Performance.
Gilbert has also appeared on Mock The Week, and he hosts a Saturday-morning show on BBC Radio Wales. In late 2008, he fronted a series of adverts to promote Welsh tourism.