"I felt like I understood them from the writing and I don't make the job very complicated for myself as an actor," said McGregor, who also had to learn how to master the distinct Fargo accent. "But when I got up there [to set], I suddenly went, 'F, I've got two jobs to do here.'"
After discussing at great length how the two characters should look with creator Noah Hawley, McGregor said he got a lot of help from his friends in the costume and makeup departments to achieve Ray's appearance. One of the longer scenes in the premiere sees McGregor as Ray in a towel, displaying the results of that work.
"I got a lot of help in terms of what they look like," he says, "but in terms of what they are, and how they sound and move, that was down to my instincts."
The Trainspotting star added, "I get dressed and I'm ready as Ray, and I start to feel like Ray. And the same as Emmit. And I just trust that."
That instinct is likely just what Hawley was looking for when he thought up the idea of having one person play his two leads.
"We wanted an actor of a certain caliber," he told THR ahead of the screening at the SVA Theater. "You need to make it a compelling job for them. But I really thought, if they're family, you want to see the family resemblance. You want to feel that they're brothers. Obviously they look very different, but there's still that inherent Ewan-ness in both."