Michael Henry "Nicko" McBrain was born on June 5, 1954 in the Hackney suburb of London, England, and took up playing drums at an early age after watching a television performance by jazz great Joe Morello, of the Dave Brubeck Quartet fame. McBrain became a dedicated practitioner of his instrument but agreed to stay in school long enough to earn an engineering degree at his parents' behest before becoming a professional musician. By the mid-'70s, he was quickly building his career resume, putting in time with blues-rockers Streetwalkers, with whom he recorded two albums (1975's Downtown Flyers and 1976's Red Card), then Canadian guitar hero Pat Travers for another pair of LPs (Makin' Magic and Putting It Straight, both in 1977), amid frequent session and road work. Come the '80s, McBrain had taken over the drum stool for rising French hard rockers Trust, recording with them on 1981's Marche ou Crève, but eventually tiring of the long distance cross-Channel commute.

In 1982, he was hired to stand in for Iron Maiden drummer Clive Burr when the latter's father passed away midway through the American leg of the band's Beast on the Road tour (McBrain had befriended the group years earlier, and actually made a cameo in Maiden's video for "The Number of the Beast" dressed as the devil). But the band was so impressed with McBrain's talents that his status was upgraded from temporary to permanent replacement by the time Iron Maiden entered Compass Point Studios in the Bahamas to begin working on 1983's landmark Piece of Mind album. And critics agreed that McBrain immediately left a mark on Maiden's sound, showcasing his uncommon single-pedal foot speed and manual dexterity on challenging numbers like "Where Eagles Dare," "The Trooper," and "Dune (To Tame a Land)." But the new boy didn't convert all of the group's fans quite as easily, because many of these were accustomed to Burr's looser, instinctive feel and more familiar metallic thudding; by comparison, McBrain's agile touch and intricate style (characterized by a tight, snappy drum sound informed by his early jazz influences) took some getting used to. Nevertheless, the drummer's unquestionable talent, tireless work ethic, and natural bonhomie would eventually endear him to all and sundry, and he has carried on performing with the group ever since, completing the "classic" lineup that oversaw their most prosperous career period, through the rough 90s and onward into their new millennium rebirth. Ironically, McBrain converted to Christianity in 1999, but this has in no way affected his involvement with Iron Maiden, despite the fact that many of the group's songs openly question fundamental biblical principles.