Then in 1975, a new Fleetwood Mac emerged with a lineup that (along with Fleetwood) included two couples: fellow Brits John McVie and his wife Christine; and the Americans Stevie Nicks and her boyfriend, Lindsey Buckingham.
Their first album together, called simply "Fleetwood Mac," included Nicks' "Rhiannon," and Christine McVie's "Say You Love Me."
The album sold five million copies. Suddenly they were rock stars.
Fleetwood was the band's manager as well as the drummer.
"It was very hard," he said, " 'cause I wasn't the classic dude, the manager, the penny pincher. I just wanted to see everyone happy, including myself. So all our assistants had limos, so we'd arrive at an airport, there'd be, like, 20 limos -- for the lighting director, you know?"
They were making it big, but coming apart. Nicks and Buckingham were breaking up, the McVies heading for divorce, and Fleetwood's marriage was ending as well, just as they began working on their second album, "Rumours."
"Were there lots of problems? Yes," said Fleetwood. "But it was never like, 'Oh my God, you're not gonna get a band.'
"A lot of people around us, our record company, people around us were going, like, 'Okay, Mick, when are you gonna break up, 'cause I don't get how you're pulling this off.' All of us! It was the music. And we weren't about to turn away from it."
The fractured relationships showed up in the songs. "Go Your Own Way" was a message from Lindsey Buckingham to Stevie Nicks; "Dreams" was Stevie's message to him.
And Christine McVie's "You Make Loving Fun" was written about her lover, not her husband.
"Falling in love, falling out of love, being betrayed in love, that's what Fleetwood Mac songs are about," said John McVie, "and that's what Fleetwood Mac is about."
"A lot, yes," added Fleetwood. "As John McVie would say, a living soap opera, 'cause we're all ex-lovers and have shared houses together, and it's a scene."
Among those ex-lovers are Fleetwood and Nicks, who began an affair while touring for "Rumours."
"I was certainly in love with Stevie," he said, "and I think it's fair to say that she was likewise."
Blackstone asked who called it off.
Nicks said, "Mick did. Because we both knew that Fleetwood Mac was gonna go on probably longer than anybody's marriage, and that it was important that we be friends, so Mick and I just put our friendship back together."