The number, the highest overnight figure in the show's history, is expected to grow after viewers watching on catchup are taken into account next week.
The series high is up 900,000 viewers on last weekend and up nearly 3 million on three weeks ago. See you all for series 5!
The long-running story line began at the start of series 4, when sex offender Michael Farmer, played by Scott Reid was charged with a string of previous killings.
But although Balaclava Man was shot dead by police, he was not named, and it turned out he was just working for a mysterious criminal network. Who exactly are these criminals, how many other "balaclava men" are still out there, and is Hilton really the so-called "H", the bent copper believed to be at the top of it all? If Roz Huntley acted completely alone the night of Ifield's death, why did she mutter "Our children need a parent..." before insisting as much?
Asean urges N.Korea to comply with global obligations
Some experts believe that Beijing is now capable of deploying combat aircraft on several of its manmade features. Plus: An amicable Asean makes Beijing more likely to conclude and comply with the COC.
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However, we remain hopeful of Macron's message of positive politics that includes diversity and open borders. A Reuters photographer there said some National Front activists were mingling in the crowd.
Walter Mazzarri hoping Watford use heavy Liverpool defeat as motivation
I am sure it was nice for him". "We need to judge the individual situation and think about what we can do with him, him, him". Captain Jordan Henderson is still injured, and Saido Mane, Ragner Klavan and Danny Ings are all long-term absentees.
Following the broadcast, Line Of Duty writer Jed Mercurio was praised by Maya Sondhi, whose character Pc Maneet Bindra was surprisingly revealed to have been involved in the drama. She said the cast were kept in the dark about the plot twists along with the audience, and that details were constantly changed throughout filming. "So things change still in the process of filming and scripts get rewritten all the time, but I had no idea about [the ending] at all".
One of the biggest assumptions that we'd make is that this marks the end of the road for Roz Huntley tonight, given that she's the target of the AC-12 investigation as opposed to being an organic part of the series itself.
Show creator Jed Mercurio said to The Mirror: "The plan is we won't shoot Line of Duty series five until next year and that means it won't be on air until 2019".