Ian McKellen and Helen Mirren are two of the world's most respected actors, yet they've never shared a screen—until now. Though the pair co-starred in a 2002 Broadway production of August Strindberg's Dance of Death, Warner Bros.' upcoming release of The Good Liar, directed by Oscar-winner Bill Condon, will mark McKellen and Mirren's first big-screen collaboration.

Mental Floss caught up with the actors—as well as Condon and several of the film's cast and crew—to spill some secrets about this taut cat-and-mouse thriller on the red carpet of its London premiere. Watch the full video below to find out which Oscar winner cuts their own hair in the bathroom... with everyday scissors.

Warner Bros. will release The Good Liar in UK theaters on November 8th, followed by its U.S. release on November 15th.