It took many years to get made, but the Irish actress Saoirse Ronan truly revelled in the power of playing “a literal boss Queen” in the new biopic Mary Queen of Scots. Except, as she shares in her Screen Test, her horse costar was an even bigger diva on set, stealing a lot of her thunder. Plus, Ronan reveals how fun the Oscars can actually be when you already know you’re not going to win.

See Soairse Ronan in "Mary Queen of Scots" out in theaters now.