The opening theme for the series was both written and produced by Elementfour, which is a collaboration between Paul Oakenfold and Andy Gray. Following the success of the first series, the theme was released as a single on 28 August 2000. The single proved to be successful, reaching number 4 on the UK Singles Chart. The theme was also featured on the soundtrack for the first series, which was released that same year. Since the series premiered, there have been numerous remixes and changes made to the song. The original theme by Oakenfeld and Gray was used through the first five series, however was later replaced by a revamped version from the sixth series onward. The song was remixed with a Christmas theme to promote "Big Brother Panto" in 2004, while a carnival themed edition was made to promote the final series to air on Channel 4. The intro to each series, which featured the theme song, was often based on the twist or theme of the house for the year. Each series is promoted with a different eye logo, with the logo also representing the theme of the house. The eye logo is meant to symbolize the phrase "Big Brother is watching" taken from the Orwell novel. The logo for the first series was a close-up of housemate Melanie Hill's eye, while the logos for the second through eleventh series' were created by Daniel Eatock. Design team Hello Charlie, who had previously created the series intros, created the eye logo for the twelfth and thirteenth series following the show's move to Channel 5. The fourteenth to eighteenth series logos were created by the design studio Shop.