Starring Benedict Cumberbatch, 'A Study In Pink' was seen by 7.05m (28.5%) on BBC One, while 479k (1.9%) watched in HD.
Earlier on the channel, The Antiques Roadshow appealed to 4.82m (24.3%) [HD: 111k/0.6%], enough to outperform Alan Titchmarsh's All The Queen's Men, which managed 2.95m (14%). At 7.30pm, 4.77m (21.6%) [HD: 143k/0.7%] watched the final Last of the Summer Wine series opener.
Meanwhile, at 8pm, the return of Countryfile interested 4.24m (16.2%) but was beaten by Heartbeat, which had 4.68m (17.9%) [HD: 168k/0.6%] for ITV1. Top Gear won the hour for BBC Two with 5.84m (22.3%), boosted by a special guest appearance from Tom Cruise and Cameron Diaz. BBC HD attracted a further 598k (2.3%) for the motoring programme.
Five's Don't Stop Believing entertained 1.09m (4.8%) between 7pm and 8.15pm, after Oliver!, which picked up 1.25m (8.3%) from 4.15pm. Following the talent show, The Mask could only hold on to 805k (3.2%).
Coast logged 3.18m (12.4%) for BBC Two at 9pm, beaten by a new episode of Taggart, which pulled in 3.74m (14.5%) for ITV1. Big Brother delivered 2.21m (8.6%) [HD: 310k/1.6%] to Channel 4 at the same time, before 1.48m (7%) [+1: 259k/2.3%] watched Alan Carr: Chatty Man. Elsewhere on the network, Amish: World's Squarest Teenager secured 2.4m (9.2%) [547k/2.1%].
BBC One won primetime with 23.5% to ITV1's 14.2% [HD: 0.4%]. BBC Two averaged a decent 13%, followed by Channel 4 with 6.8% [+1: 1.1%], and Five with 3.9%.
BBC Three had a fantastic night, as Family Guy topped the multichannel ratings with 984k (4.2%) and 1.13m (5.8%) at 10pm and 10.20pm. Prior to that, Toy Story 2 took 1.01m (4.4%) between 7.30pm and 9pm.
BARB ratings data supplied by Attentional