As any Fleetwood Mac fan will tell you, it's common for members of a band's classic lineup to get back together years later and run through their biggest hits. But what about a lineup that had yet to be discovered? That's what happened on Saturday, when four of the five men who comprised Iron Maiden back in 1977 took the stage at a London club.

The reunion was the work of Maiden77, a website devoted to the band's early years. The site arranged for Dennis Willcock (vocals), Tony Moore (keyboards) and Barry "Thunderstick" Purkis (drums) to join guitarist Terry Wapram at the Hope and Anchor, where Wapram's band, Buffalo Fish, was performing. The only person missing from the equation was Steve Harris, the bassist and only constant member of Iron Maiden throughout their 40-year history.

As Maiden77 wrote on its Facebook page, "We had been planning something, but to be honest did not know if we could pull this off a -- reunion of 80 percent of the 1977/1978 lineup ... Thank you, guys. It was an amazing night."

The inclusion of Moore was particularly interesting. According to band lore, he played only one (unsuccessful) gig with Iron Maiden, after which it became apparent to all that keyboards didn't actually fit in with their sound. Moore later became a touring keyboardist with Cutting Crew. Purkis also left at some point in 1977, but Willcock and Wapram stayed in the band for another year. Iron Maiden would undergo a few more lineup changes before they released their self-titled debut in 1980.

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