Heathen is the twenty-second studio album by David Bowie. The album was considered a comeback for him in the US market; it was his highest charting album (#14) since Tonight (1984), and earned some of his strongest reviews since Let's Dance (1983). Worldwide, it sold over two million copies and experienced a four-month run on the UK charts. Although its production had started before September 11 attacks in 2001, the album was finished after that date, which resulted in the influencing of its concept. Heathen marked the return of record producer Tony Visconti, who co-produced (with David Bowie himself) several of Bowie's classic albums. The last album Visconti had co-produced was Scary Monsters in 1980. Originally, Bowie had recorded the album Toy for release in 2000 or '01. This album was meant to feature some new songs and remakes of some his lesser-known songs from the 1960s. Although Toy remains officially unreleased, a few of its tracks—including "Afraid" and "Slip Away" (then titled "Uncle Floyd")—appear on Heathen. Some other re-recorded songs were included as B-sides to the singles from Heathen. The album features guest appearances from The Who guitarist Pete Townshend (who had played guitar on an earlier Bowie track, "Because You're Young" from Scary Monsters (and Super Creeps)), Foo Fighters frontman Dave Grohl, Dream Theater keyboardist Jordan Rudess, pianist Kristeen Young, and prolific bassist Tony Levin of King Crimson. The song "I Took a Trip on a Gemini Spa