After the success of What Will the Neighbours Say?, which was solely produced by Brian Higgins and Xenomania, the production team was asked to create Girls Aloud's third studio album.
Alexis Petridis of The Guardian wrote that Chemistry is "a record that dispenses with the tiresome business of verses and instead opts for songs apparently constructed by stitching eight different choruses together.
"[2] BBC Music exclaimed that Girls Aloud "have resuscitated its corpse by wedding chart-friendly melodies to experimental avant-garde sounds".
[3] The album takes influences from a wide variety of sources, including "everything from French chanson to piano-pounding blues to the clipped R&B of the Small Faces".
"[4] The songs are noticeably less rooted in electronic music, although "Swinging London Town" is "a dark, squiggly synth pop epic" and "It's Magic" is composed of "little Röyksopp-like keyboard riffs".
[7] The Guardian said that the album's "lyrics sound like Blur's Parklife rewritten by the editorial staff of Heat magazine" and "holds a distinctly ambiguous mirror up to noughties celebrity.
"[1] "Models" was also criticised for its use of the word "shit",[7] while "Swinging London Town" allegedly "toys with the girls' reputation for partying a little too heartily.
[4] One reviewer called "Biology" "the most faithful to this album's spirit of innovation, blending the kind of saucy cabaret you'd expect to find in a gin-soaked saloon bar with a glorious chorus of fizzing, gliding synths and deceptively breakneck beats.
"[10] "Wild Horses", track four on the album, "features a mock choirgirl intro segueing into a breezy acoustic-rocker [...] like a harder St Etienne.
[4] The version, described as "the obligatory Christmas ballad",[10] was largely slated for its lack of creativity and similarities to their 2004 cover of The Pretenders' "I'll Stand By You" (although some critics preferred it).
[13] "Long Hot Summer" was called "effervescent but relatively unexciting",[17] as well as a "well-produced, upbeat pop tune, with a great hook in the chorus" by The Sentinel.
It was called "a dark, squiggly synth pop epic a la Pet Shop Boys on the diverse characters – from wannabes to trustafarians – found in the nation's capital",[4] and that there "hasn't been a song since the Pet Shop Boys' 'West End Girls' that captures the ugly charms of London on a Friday night, but 'Swinging London Town' comes close.
"[11] It was further described as "a collision of warp-speed funk guitar riffs and distorted Giorgio Moroder-style techno-disco that unexpectedly drops into wafting movie-soundtrack ambience.
"[2] "It's Magic", a Nicola Roberts solo which was called "the album's hidden highlight", was labelled "weighty, sultry electro-pop [...] layered with beautifully enticing synth melodies.
[11] The album's closer, "Racy Lacey", is "a portrait song of a young lady in the style of Prince's "Darling Nikki" or Blur's "Tracy Jacks.
[19] The bonus disc contains Christmas music, including covers and original songs produced by Xenomania under the moniker Randy Snaps.
The album's first single was "Long Hot Summer", released in August 2005 as a "buzz" track to regenerate interest in the girls.
The plans fell through, but the music video had taken inspiration from the movie's car theme and Girls Aloud portrayed mechanics.
"[3] Virgin Media gave the album five stars, saying it was "bursting [...] with invention, quirky lyrics, tongue-in-cheek sauciness and [...] appeals to grown-up pop fans and music critics as well as to the teenyboppers.
[27] In comparison to Girls Aloud's previous albums, Entertainment.ie referred to Chemistry as their "best offering yet [...] overflowing with pop hooks, sassy production and choruses just waiting to take up permanent residence in your head.