Mathew James Willis (born 8 May 1983), also previously known as Mattie Jay, is an English musician, singer, songwriter, television personality and actor, best known as the bassist and the co-vocalist of the pop band, Busted. Willis released his debut solo album Don't Let It Go to Waste on 20 November 2006, which included three top 20 singles.
In December 2006, Willis won the sixth series of the ITV reality series I'm a Celebrity...Get Me Out of Here!, and later went on to co-present the ITV2 spin-off show with his wife Emma in 2007 and 2008. In 2014, Willis played the role of Garth Stubbs in the revived ITV sitcom Birds of a Feather and Luke Riley in the BBC One soap opera EastEnders.