The episode 'Heart of Darkness' attracted 358k (1.6%) from 9pm on ITV2 before picking up a further 147k (0.9%) on timeshift.
Elsewhere on the multichannels, Touch took 341k (1.5%) on Sky1, and Mad Men had 50k (0.2%) on Sky Atlantic.
The terrestrials saw Crimewatch dominate the 9pm hour with 4.61m (20.7%).
On ITV1, The Hunt for Bin Laden averaged 2.2m (11%) with an additional 205k (1.5%) on +1. Earlier, William and Kate: The First Year grabbed 3.84m (16.8%) from 8pm (+1: 405k/1.8%).
BBC Two showed Hairy Bikers' Bake-ation (2.7m/11.8%) and Meet the Romans with Mary Beard (1.88m/8.4%).
On Channel 4, Supersize v Superskinny was watched by 1.43m (6.3%) from 8pm (+1: 275k/1.2%). Hidden Talent followed with 1.06m (4.8%) and 182k (1.1%) on timeshift.
CSI continued to impress for Channel 5 with 1.81m (8.1%) and 160k (0.9%) on +1. CSI: NY managed 1.22m (7%) in the 10pm hour, and War Hero in My Family managed 1.03m (4.5%) earlier from 8pm.
Overall, BBC One came out on top in primetime with 24.1% ahead of ITV1's 15.3% (+1: 0.9%). BBC Two took 7.9%, with Channel 5's 5.4% (+1: 0.3%) beating Channel 4's 4.4% (+1: 0.9%).
BARB ratings data supplied by Attentional