Among the trove of Beatles lore, one item that rarely gets mentioned is how Paul McCartney made an instrumental album in 1971, released it in 1977, and then kept the entire episode a secret until 1989. As reported by Ultimate Classic Rock (via Dangerous Minds), Sir Paul recorded an instrumental version of his Ram album just one month after the release of that LP, employing the pseudonym Percy “Thrills” Thrillington. He titled the album, simply, Thrillington.

Six years later the record was quietly released, but even then, McCartney made no effort to take credit for it. Finally, during a press conference in Los Angeles in 1989, a writer broached the topic. “What a great question to end the conference!” said McCartney. “The world needs to know! But seriously, it was me and Linda – and we kept it a secret for a long time, but now the world knows! You blew it!”

McCartney also penned the liner notes for the album, using the pseudonym Clint Harrigan. You can read the story in full at the Dangerous Minds website.