Benedict Cumberbatch and Keira Knightley tackle some serious mathematical equations on-screen -- he as Alan Turing, the legendary British scholar and father of the modern computer, she as Joan Clarke, one of his protégés, in the new film "The Imitation Game" -- but, no, they're not exactly math whizzes when the cameras stop rolling.
"I didn't understand any of the maths," Knightley recalled, laughing, at a recent London news conference. (Brits say "maths," not "math," when abbreviating "mathematics.")
"I understood a little bit," Cumberbatch admitted. "But if you put an algorithm in front of me now, even a quadratic equation ... this press conference would] go on far too long."
The film, which opens Friday, tells the gripping, true story of Turing and a ragtag team of British math nerds who secretly struggle to break the Nazis' infamous "Enigma" code during World War II. Meanwhile, Turing has a secret of his own -- he's gay, at a time when homosexuality is a criminal offense.
Cumberbatch is no stranger to quirky, complicated geniuses. He also plays Sherlock Holmes in the BBC's popular "Sherlock" series.
"There's a great broad romance to ... maths and physics," Cumberbatch said.
Math ... romantic? It can be, or so say plenty of filmmakers out there who have a passion for math and mathematicians. Here are just a few examples, on big screens and small.
A BEAUTIFUL MIND Russell Crowe stars as John Nash, the controversial Nobel Prize winner who suffered from paranoid schizophrenia. The 2001 film won four Oscars.
GOOD WILL HUNTING The beloved 1997 tale of a working-class South Boston math prodigy (Matt Damon), his pal (Ben Affleck) and a therapist (Robin Williams). Oscars went to Williams (best supporting actor) and Damon-Affleck (best original screenplay).
THE BIG BANG THEORY OK, technically Jim Parsons and Johnny Galecki play physicists, but this uber- popular CBS sitcom proves geeks don't finish last (at least not in the Nielsen ratings).
EINSTEIN'S BIG IDEA A rather engrossing 2005 PBS docudrama explaining just what E=mc2 means, and the twists of fate that led Albert Einstein to dream up arguably the world's most famous equation.
MATHS IN THE MOVIES Clever, kooky YouTube videos from Matt Parker, an Aussie "stand-up mathematician" (yep) who points out math errors in films like "Transformers" and "Fast & Furious."