As part of Capitol's shift in marketing strategy for Duran Duran to develop into a dance band over the course of 1982 (in a bid to shift more units of the Rio album), it was decided to release an EP of remixed tracks in various territories globally to capitalise on increased night-club play and to try to replicate that success on radio.

Part of this strategy also involved producer David Kershenbaum remixing various Rio tracks. Most of these remixes also appeared on the Carnival release as well as various twelve-inch singles.

The demand for Duran Duran material during the autumn of 1982 was quite high. DJs who heard the new mixes could not get enough, and started to put the dance mixes on the air. During the week of 2 October, the US version of the "Carnival" EP actually entered the album charts at #98. It was gone by the following week.

The success of the "Carnival" EP gave the band enough clout to bring Kershenbaum back in to remix the entire A-side of the Rio album, which was duly released in the USA in November 1982.

Because Carnival was meant to capitalise on Duran Duran's burgeoning dance-oriented success, the track listing around the world differed from region to region.

The Dutch EP, released in a white sleeve with photos taken from the Rio tour book, featured twelve-inch versions – or "Night Versions" in early Duran Duran parlance – lifted from four of the band's more popular singles – "Hungry Like The Wolf", "Rio", "Planet Earth" and "Girls on Film". A rare misprint of the Dutch sleeve is existing, stating "Hold back the rain" to be included instead of "Planet earth".

The Night Version of "Girls on Film" is actually slightly different from the version that appeared on the EMI twelve-inch single, clocking in at just around 15 seconds longer. Also, the David Kershenbaum Night Version mix of "Rio" was commercially exclusive to this EP (it also featured on an American promo twelve-inch), as the "Rio" twelve-inch single featured "Rio (Pt II)" as the lead mix.

The Spanish EP featured, on the sleeve at least, the same running order as the Dutch EP. Closer inspection however, shows that the version of "Rio" is actually just the album version, although it's listed as the Night Version. The song titles on the Spanish release were all translated into Spanish.

For the North American release – released both in Canada and the US – the track listing changed slightly, incorporating among other things, a new Kershenbaum mix of minor single "My Own Way" which featured additional lyrics left off the original album version as well as the 'rhythm section punched up, making it ideal for dancing'. This mix eventually resurfaced on the Kershenbaum version of the "Rio" album in November 1982.

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Wikipedia