Million watch BB housemates' return
The return of some of Big Brother's most famous housemates attracted 5.1 million viewers to Channel 4.
The show, in which Josie was crowned winner before she walked back into the house with previous Big Brother stars, scooped an average of 4.1 million (18.2%) viewers.
The audience peaked at 5.1 million just after 10pm, when previous housemates, who include "Nasty" Nick Bateman, Makosi Musambasi and sex-change Big Brother 5 winner Nadia Almada, started to go into the house, and again near the end of the show.
Channel 4 said that Tuesday night's 4.1 million was 66% up on the current series average of 2.5 million.
Last year's finale, which was won by Sophie, was watched by just 2.9 million (15.8%) of viewers.
Ultimate Big Brother will run for 18 days before the reality format leaves Channel 4.
Returnees include Nikki Grahame, Ulrika Jonsson, Brian Dowling, rapper Coolio, racing pundit John McCririck, and divorcees Chantelle and Preston, who split after just nine months of marriage.