Kenneth Branagh's stunning and uncanny transformation for brand-new Sky series This England shocked viewers when they first saw his look unveiled.
Now, a new featurette has been released which includes interviews with cast members and the show's writer Michael Winterbottom, explaining how the transformation was achieved.
In the video, Branagh says that playing Boris was a "life-changing part" for him, before explaining that his approach to the role was to "read everything that he had written, in addition radio programmes and interviews, examples of how he dealt with difficult questions".
Branagh continues: "I suppose essentially the goal was to try and find how he, by his own hand, expressed himself to the world." You can watch the full video right here now.
Winterbottom and Branagh go on to talk about the "physical preparation" involved in playing the character, as well as the prosthetics and make up, which Branagh says took between "two and three hours".
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The rest of the cast all explain that because of this they never actually met Branagh as himself - by the time they saw him each day he was already in the Boris make-up.
After discussing the level of improvisation involved in each scene, with each actor described as an "expert" in their own character, Winterbottom says that he's not sure "we would have ever made the series" if Branagh "hadn't said yes to doing it".
This follows Ophelia Lovibond explaining her own process for developing her role, and discussing exclusively with RadioTimes.com why she didn't reach out to the real Carrie Johnson before playing her.
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