More than six decades after he adopted the stage name Michael Caine, Maurice Micklewhite has made it official, the Guardian reports. The 83-year-old actor (and former Micklewhite) tells the Sun that it was ISIS and the resulting heightened airport security that prompted him to finally make his showbiz name his legal name. Airport security guards "would say, 'Hi Michael Caine,' and suddenly I’d be giving him a passport with a different name on it. I could stand there for an hour. So I changed my name,” Caine explains.
Per the Telegraph, the then-Micklewhite chose the name Michael Caine in 1954, lifting the surname from a poster for the film The Caine Mutiny. According to the Guardian, his first pseudonym was "Michael Scott," but he had to change it upon moving to London and discovering there already was an actor of that name. (More Michael Caine stories.)