The figure is down around 260k on last Thursday's episode and 1.17m on the equivalent episode from 2008's run, which was shown in an earlier 9pm slot.
Big Brother was still Channel 4's most popular programme in primetime and built on the 1.87m (8.2%) audience for How The Other Half Live in the 9pm hour. Earlier, at 8pm, The Home Show drew 1.68m (8.1%).
BBC One suffered in the 8pm hour against ITV1's soaps double bill. As Seen On TV took 2.7m (13.6%) in the first half of the hour, then the audience dropped to 2.5m (11.7%) for The Rat Pack at 8.30pm.
At 9pm, BBC One's audience rocketed to 6.93m (30.5%) for the latest episode of New Tricks, outrating The Bill's 3.64m (16%) for ITV1.
Rick Stein's Far Eastern Odyssey appealed to 2.44m (11.8%) on BBC Two at 8pm, then Mock The Week brought in 2.21m (9.7%) at 9pm.
Five's Extreme Fishing With Robson Green caught 478k (2.3%) in the 8pm hour, after which The Mentalist picked up 1.58m (6.9%).
BBC One averaged 23.7% to lead primetime, while ITV1 put in 21.6%. Channel 4 was third with 8% (+1: 0.9%), followed by BBC Two with 8.2% and Five with 4.6%.
BARB ratings data supplied by Attentional