But, for mine, Then Play On, along with the non-album singles Oh Well and The Green Manalishi (With the Two-Prong Crown) represented the high water mark as chemical issues started to kick in big time.
One suspects that Green had never been totally stable, but under the influence of LSD he developed a desire to donate all of the band's money to charity. Predictably, the others disagreed, and Green played his last show with Fleetwood Mac was on 20 May 1970.
The band still had Spencer and Kirwan on board, and strengthened the lineup with Christine McVie (née Perfect) who formally came on board in 1970 but had been playing sessions since Mr Wonderful and had joined them on stage (on and off) since a gig at Bristol University in May 1969. She was, after all, married to the bass player. In the meantime she'd left Chicken Shack, cut a solo album (Christine Perfect) and managed a reasonable hit in Britain with a cover of Etta James' I'd Rather Go Blind .She also contributed the artwork for Kiln House, the new line-up's initial offering.
Her first gig after she'd been officially invited to join the band was in New Orleans 6 August 1970.
But the changes kept coming. Jeremy Spencer left the group's hotel in Los Angeles in February 1971 to get a magazine, and ended up in the Children of God. Peter Green was drafted in to finish the US tour, but that was never going to be a permanent arrangement.
So they needed a new guitarist, ended up with Bob Welch who they managed to hire without actually hearing what he did, and released Future Games in September 1971, following it up six months later with Bare Trees. Both were significant stylistic departures from what had gone before and things were confused further by a CBS release, Fleetwood Mac's Greatest Hits which was, predictably, predominantly Peter Green material.
Bare Trees was well received, but was mostly written by Kirwan, who was heading into issues with alcohol dependency and ended up getting fired by Mick Fleetwood. At that point things became really confused as lineups got reshuffled. Manager Clifford Davis (who claimed to own the name Fleetwood Mac) claimed Welch and John McVie had quit and put a bogus outfit out on the road. Fleetwood and Christine McVie were allegedly going to join up with this crew a little later.