Cold War had an overnight audience of 5.7 million viewers, a share of 26.7% of the total TV audience.
Doctor Who was again third for the day. where top honours were taken by the return of ITV's talent show, Britain's Got Talent, which had 10.5 million watching and a massive 41.5% share of the audience.
The BBC's talent show, The Voice, had 6.7 million watching.
Doctor Who once more won the time-slot with You've Been Framed! And Famous 4 getting 4.0 million watching.
Final ratings will be released next week, which should see Doctor Who substantially increase its rating once those who timeshift the programme are factored in.