This chart countdown celebrates the biggest selling singles of 1975, the best pop videos, the artists who appeared in them, and the stories behind the songs - from Roxy Music and the Carpenters to Queen and David Bowie. Leo Sayer, Candi Staton, Dana, Tony Christie, Paul Gambaccini, and other famous faces guide viewers through the biggest hits of the year. Dave Bartram from Showaddywaddy recalls their chart toppers, while members of Mud, 10cc and the Bay City Rollers reminisce about their hits