Genesis's original lineup has reunited for the first time in three decades. Peter Gabriel, Phil Collins, Tony Banks, Steve Hackett and Mike Rutherford are co-operating on feature-length documentary for the BBC, titled Genesis: Together and Apart.

This new film has yet to receive an air date, but the prog quintet have already posed together for a press photo – their first joint shoot since 1998. According to a statement, the movie will combine recent interviews with unseen archive footage and rare performance material.

Despite the huge gap between a television documentary and a full-scale tour, many Genesis fans are wondering whether this announcement is a sign of bigger things to come. 2014 marks the 40th anniversary of the group's seminal album The Lamb Lies Down on Broadway, and Collins, who appeared to have given up music, made his live return at a school concert in May. "I think there’s a small chance [we could reunite]," Gabriel told Rolling Stone in April, "but I don't think it’s very high."

Gabriel is arguably Genesis's most evasive member. Although he co-founded the band in 1967, he left in 1975; Collins became the new singer, leading the group through their more pop-oriented 1980s run. The five musicians haven't performed together since a brief encore on stage at Milton Keynes in 1982. Even 10 years ago, Gabriel pulled out of a proposed comeback: "I could feel the suction of the black hole," he said later.

For now, the possibility of an original Genesis tour is hampered by several members' prior gig commitments: Gabriel has solo concerts in chunks throughout 2014, and Rutherford's band Mike and the Mechanics recently announced shows in April and May 2015.