It's her biggest audience yet, and 1.3 million above the average figures for her second series.
The figure represented 21 per cent of the 9pm audience - and also eclipsed the 3.5 million ratings for the launch episode of Extras' second series Extras last month, in which Ricky Gervais parodied Tate's brand of catchphrase comedy.
Jack Dee'sLead Balloon also proved a popular BBC Two transfer, with 2.6 million viewers and an 12 per cent share at 9.30pm. It was hastily moved to the terrestrial channel following a successful launch on BBC 4 a month ago.
A new fourth episode, which aired on BBC4 at 10pm, pulled in 112,000 viewers.
