Penned by Peep Show writers Jesse Armstrong and Sam Bain, the programme appealed to just 2.89m (13.9%) at 9.30pm. This represents a 440k audience drop since its premiere rating a fortnight ago.
Earlier at 8.30pm, Celebrity Masterchef picked up 3.68m (17.4%) for the channel, after which My Family averaged 4.04m (18.9%). Meanwhile, at 10.35pm, the fourth series launch of Would I Lie To You? had 3.12m (19.7%).
Channel 4's Big Brother grabbed 2.3m (10.9%) [+1: 222k/1.3%] and 2.54m (15.7%) [+1: 237k/2.5%] at 9pm and 10.30pm respectively, while The IT Crowd amused 1.79m (9.4%) [241k/1.9%] at 10pm.
Dickinson's Real Deal averaged 2.58m (12.9%) for ITV1 between 8pm and 8.30pm. Later at 9pm, Doc Martin's fourth series catch-up held up with 3.09m (14.7%) [104k/0.5%].
Over on Five, Nature Shock, The Mentalist and CSI: NY were watched by 764k (3.7%), 1.95m (9.3%) and 1.02m (5.7%) at 8pm, 9pm and 10pm.
Gardeners' World took 1.68m (8%) for BBC Two at 8.30pm, then Monsoon Railway managed 1.64m (7.8%), and 1.1m (5.4%) tuned in for a repeat of Coast at 9.45pm.
Overall, BBC One edged ITV1 in primetime with 20.5% to 20.3%, while Channel 4 was third with 7.5% [+1: 0.7%]. BBC Two followed with 6.3%, and Five was last with 5.1%.
BARB ratings data supplied by Attentional