Fifty years after Britain's foremost underground band released their debut album Piper at the Gates of Dawn, Pink Floyd remain one of the biggest brand names and best-loved bands in the world. This film features extended archive footage, some of it rarely or never seen, alongside original interviews with the four surviving members of Pink Floyd - David Gilmour, Roger Waters, Richard Wright and Nick Mason - and traces the journey of a band that has only ever had five members, three of whom have lead the band at different stages of its evolution.

A band that has spanned 40 years pioneering everything from underground rock to the stadium extravaganza, a band that has survived tragedy and shunned celebrity and wrestled publicly with both it's success and it's audience. There have been five members of the band three of which have lead the band in different decades and that's why the question still remains, which one is pink? This film examines the band and it's history in order to discover how they became so successful.