"It sounds so pretentious," the actress tells Marie Claire, "but he learned his commands in French."
Mendes, 37, brought her Belgian Malinois, Hugo, along for her cover interview at L.A.'s Griffith Park, and the "rather intimidating" dog instantly obeyed Mendes's orders for him to coucher, or lie down.
Wearing a beeper-controlled behavior-modification collar, Hugo trails Mendes most places. She told PEOPLE last year that security was her primary concern: "He's an attack dog," she said, "a guard dog," but also added that "he's really sweet."
Such a fearsome pooch requires a little extra attention when it comes to his caretakers. Enter Dog Whisperer Cesar Millan, whom Hugo counts as a dogsitter.
Hugo has other famous friends, too. He's grown close to Mendes's boyfriend Ryan Gosling, while Mendes has brought Gosling's dog, George, under her wing.
As for Mendes, she prefers to stay tight-lipped about The Place Beyond the Pines castmate Gosling, saying only that, "He's your dream costar. I have never felt so creatively satisfied on a film."
Courtesy Marie Claire