The origin story of Ludwig Dieter, the German safecracker from Zack Snyder’s ‘Army of the Dead,’ is instantly forgettable LONDON: Ever wondered how Ludwig Dieter, the eccentric German safecracker from Zack Snyder’s “Army of the Dead” movie, came to develop his deft lockpicking skills? No? Me neither. But Snyder and Matthias Schweighöfer (who played Dieter and directs this bizarre prequel) obviously did. And now they’ve decided to tell us. So, “Army of Thieves” reintroduces us to Dieter, six years before the events of Snyder’s zombie heist movie. Dieter goes by his real name, Sebastian, and dreams of escaping his mundane life as a bank teller in Potsdam, Germany. He posts videos to YouTube explaining the history of famous safe designers (all while acting as a handy, but clunky, exposition device for the movie), but nobody ever watches them. One day, however, a mysterious and glamorous thief comments on his videos, inviting him to take part in an underground safecracking contest — because there’s no easier/lazier way to ascertain that a character is extremely skilled at something than have them compete in a frankly ridiculous competition in a grimy basement. As it turns out, the thief is Gwendoline (Nathalie Emmanuel) and she’s looking to recruit a safecracker to join her team of specialists as they undertake a series of heists across Europe. Will the naïve Sebastian join her and become the highly skilled mercenary we meet in “Army of the Dead”? Yes. He will. It would be a short prequel if he didn’t. “Army of Thieves” is a film that simply doesn’t need to exist. It’s a backstory no one asked for designed to flesh out a character that no one needed fleshed out. And it does that without any of the best bits of Snyder’s zombie movie — the zombies and Dave Bautista. What’s more, it does it in a depressingly obvious way, using every tried-and-tested movie trope in the book. Schweighöfer does a decent job behind the camera but is pretty irritating in front of it. As a result, “Army of Thieves” winds up being a serviceable, though instantly forgettable, heist movie. And there were already plenty of those.