BBC Two's celebrity special of the hit reality show, which concludes on Thursday, opened with 3.82m (14.9%) between 8.30pm and 9.30pm - University Challenge (3.14m/11.7%) and Natural World (1.86m/7.9%) also aired on the channel.
Popular sitcom Miranda, airing between 9pm and 9.30pm, fell 700,000 week-on-week to 6.39m (23.1%) but still won its slot for BBC One.
Mrs Brown's Boys followed with an impressive 7m (26.5%) at 9.30pm, losing 300k in comparison. Panorama returned to its 8.30pm slot with 3.53m (13%).
Meanwhile, ITV's Lewis continued to challenge with 5.9m (21.9%) watching the detective spinoff's latest instalment in the 9pm hour, adding 379k on +1. Earlier at 8pm, Cornwall with Caroline Quentin interested 3.62m (13.5%).
Elsewhere, Embarrassing Bodies entertained 1.29m (4.8%) for Channel 4 from 9pm (+1: 272k), after which 1.24m (6.8%) caught What Happens in Kavos at 10pm (+1: 246k). However, Dispatches was the broadcaster's most-watched show with 1.91m (7.1%) from 8pm (+1: 225k).
Overall, ITV won primetime with 24.2% (+1: 0.7%) over BBC One's 22.8%. BBC Two clinched third place with 8.7%, beating Channel 4's 4.8% (+1: 0.7%), and Channel 5's 4.3% (+1: 0.5%).
> Coronation Street, Hollyoaks boosted by Kirsty, Esther plots
BARB ratings data supplied by Attentional