Top Boy, a four-part drama starring Ashley Walters and Kane Robinson as drug dealers on an east London estate, launched with 1.13m (6.5%) from 10pm and 126k (1.5%) on +1.
On BBC One, an audience of 4.06m (15.9%) tuned in from 9pm to watch Ben Fowler become the latest candidate to be fired by Lord Alan Sugar in the second series of Young Apprentice.
The programme was roughly flat on its opening episode last week, but proved no match for drama Doc Martin, which appealed to 8.69m (34.1%) on ITV1 and 260k (1.4%) on +1.
Inside Out had 3.18m (14.1%) on BBC One from 7.30pm, and Panorama mustered 3.43m (13.7%) from 8.30pm. A Question of Sport fetched 2.42m (15.9%) from 10.45pm, while ITV1's Exposure was seen by 1.65m (13.5%).
Brave New World with Stephen Hawking captivated 730k (3%) on Channel 4 from 8pm, and Attack of the Trip Advisors delighted 1.17m (4.6%) from 9pm and 228k (1.3%) on +1.
Celebrity Antiques Road Trip enthralled 1.97m (9%) on BBC Two in the 7pm hour. University Challenge and Home Cooking Made Easy grabbed 3.14m (12.9%) and 2.23m (8.9%) respectively in the 8pm hour. Origin Of Us delighted 1.4m (5.5%) from 9pm and Never Mind The Buzzcocks amused 1.68m (8.4%) from 10pm.
Celebrity Wish List took 241k (1.1%) from 7.30pm, and The Gadget Show switched on 959k (3.9%) in the 8pm slot. The new series of The Hotel Inspector booked in 959k (3.9%) from 9pm. Big Brother attracted 1.28m (7.1%) in the 10pm hour, before Big Brother's Bit On The Side entertained 488k (5.3%) from 11pm.
Overall, ITV1 dominated primetime with 28% (+1: 0.6%) against BBC One's 18.7%. BBC Two took third with 8.1%, followed by Channel 4's 4.2% (+1: 0.6%) and Channel 5's 3.8%.
Elsewhere, Only Connect quizzed 630k (2.5%) on BBC Four from 8.30pm. Hell's Kitchen USA continued with 415k (1.6%) on ITV2 from 9pm and 185k (1%) on +1.
BARB ratings data supplied by Attentional