The first episode of the trilogy, which chronicles the legacy of the Yorkshire Ripper murders, averaged 2.45m (12.2%) for Channel 4 between 9pm and 11.15pm.
Billy Connolly: Journey To The Edge Of The World continued to perform well for ITV1, with the third episode pulling in 4.09m (17.8%) during the 9pm hour. It was just ahead of BBC One's New Tricks, which logged 4.03m (17.5%).
1.66m (7.2%) tuned in to watch the first episode of Darwin's Dangerous Idea on BBC Two, while Five's urban documentary series Soho Blues logged 959k (4.2%), putting the channel in last place in the timeslot.
BBC One performed well during the first half of the 8pm hour, drawing 5.59m (25.2%) with Rogue Traders. The audience dropped to 4.38m (18.8%) at 8.30pm when the final episode of The Green Green Grass was shown.
Over on ITV1, The Bill - which is soon to be cut down to one episode a week - drew 4.56m (20.1%), while 2.1m (9.3%) tuned in to watch the first episode of Jimmy Doherty in Darwin's Garden on BBC Two.
Five was last for the 8pm hour, pulling in a disastrous 243k (1.1%) for the new series, Stylista, which follows 11 interns as they compete to work on the American edition of Elle magazine.
BBC One led primetime with an average share of 23.1%, beating ITV1's 18.1% share. Channel 4 was third with 9.6% (+1: 0.8%), followed by BBC Two with 7% and Five with a poor 3.1%.
Elsewhere, Skins continued to perform well for E4, drawing 764k (4.8%) at 10pm.
At 9pm, Sky1's screening of the new Bones took 590k (2.8%), just beating ER, which grabbed 569k (2.7%) for More4.
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Ratings data supplied by Attentional