4

Originally titled Silent Partners, the 4 refers to the album number and the reduced four-piece. Jones and Gramm wrote all the songs. The session players included Thomas Dolby on main synthesizers, Larry Fast, Bob Mayo, Michael Fonfara, Hugh McCracken and Mark Rivera, with Junior Walker's saxophone solo on "Urgent" and backing vocals by Ian Lloyd and Lange. Dave Wittman engineered, Tony Platt recorded basic tracks and George Marino mastered. Recording ran about eight months, with the studio start time drifting from noon to midnight, which inspired "Night Life"; Lange left before the end for Def Leppard's High 'n' Dry. A Hipgnosis cover was rejected as too provocative. It was number 1 on the Billboard 200 for ten weeks, 5 in the UK, and sold six times platinum in the US. AllMusic gave 4.5 stars and Classic Rock called it the band's masterpiece. A four-disc Rhino deluxe edition on September 12, 2025 has a 2025 remix by Wyn Davis and Steve Ornest, produced by Jeff Pilson, and unreleased songs.