Upon its release in the UK, 25 O'Clock sold twice as many copies as XTC's then-latest album The Big Express (1984), even before the Dukes' identity was made public.

When guitarist Dave Gregory was invited to join XTC in 1979, bandleader and songwriter Andy Partridge learned that they both shared a longtime passion for 1960s psychedelic music.

An album of songs in that style was immediately put to consideration, but the group could not go through with it due to their commercial obligations to Virgin Records.

During the making of their 1984 album The Big Express, Partridge began writing material he thought could potentially be performed in a psychedelic style, the first being "Your Gold Dress".

[4] In November 1984, one month after the release of The Big Express, Partridge traveled to Monmouth, Wales with engineer John Leckie to produce the album Miss America by singer-songwriter Mary Margaret O'Hara, who had recently signed with Virgin.

Partridge and Leckie were dismissed due to conflicts related to their religious affiliations or lack thereof (O'Hara was a devout Catholic).

[5] Partridge was feeling inspired by Nick Nicely's 1982 psychedelic single "Hilly Fields (1892)", and devised a recording project to fill the newfound gap in his schedule.

Partridge invited his XTC bandmates to participate; they were augmented on drums by Dave Gregory's brother Ian, since the group did not have a drummer at the time.

[4] After the label reluctantly loaned the group £5,000, two weeks were spent on the album's recording and mixing at Chapel Lane Studios in Hereford, England.

[11] Released exclusively in Britain on April Fool's Day 1985, the mini-album was presented as a long-lost collection of recordings by a late 1960s group.

[9] Virgin Records publicised the Dukes as a mysterious new act,[18] and when asked about the album in interviews, XTC initially denied having any involvement.

", by Colin MouldingA remastered and expanded version of 25 O'Clock was released on 20 April 2009 by Partridge's Ape House record label.