A city fox freezes in an alley, startling a thief and signaling the wiliness of "Fuze," a movie whose plot mechanics are as precisely calibrated -- and at times as incomprehensible -- as the machinery of the unexploded bomb at its center. That device, seemingly a rusty World War II relic thrusting from the mud of a Central London building site on the Edgware Road, might be lethal but it's not the point: It's a diversion for a crime that's been a long time in the planning.
The film's framing is not nearly as preposterous as sections of its plot: Wartime explosives, often found by construction crews, are not uncommon in London. Within minutes, this amiably daffy thriller, energetically directed by David Mackenzie, is all business as the police and military swing into action. While an efficient police superintendent (a squandered Gugu Mbatha-Raw) arranges an evacuation of the area and shuts off its electricity, a steely Army sniper and bomb disposal expert named Tranter (Aaron Taylor-Johnson) examines the device and makes plans for a controlled detonation. Then a sharp-eyed young corporal notices something strange about the now-ticking bomb, which Tranter seems oddly unwilling to investigate. Is this even a wartime explosive?
The thieves in the basement of a nearby building may know something about that. Led by a diamond expert (Theo James) and the mysterious X (Sam Worthington), they're after the safe-deposit vault of a now-deserted bank. I was grateful, though, for their bright orange workmen's coveralls -- when multiple characters in an action movie are young, handsome, brunette and bearded, I can't be the only viewer who gets confused.
Moving from the police command center to the bomb site to the robbery-in-progress -- and eventually to Turkey -- "Fuze" hurtles along entertainingly and with no small amount of tension. Thoroughly researched police and Army protocols mostly maintain credibility; but the soundtrack is disappointingly generic and the movie's high-caliber cast (notwithstanding a brief, admittedly pleasing final reveal) has little of substance to play. Despite a plot (by Ben Hopkins) bursting with double- and triple- crosses, the movie feels programmatic, its characters bland cogs in a Rube Goldberg machine.
Thank goodness, then, for the cinematographer Giles Nuttgens, who grounds the action in a city teeming with diversity and saturated in surveillance. Mackenzie, a British director whose résumé strides across genres and locations, seems mainly drawn to stories about men's work; like his most popular movie to date, "Hell or High Water" (2016), "Fuze" is bereft of fleshed-out female characters. So a terrific performer like Mbatha-Raw is left to interact with screens and look increasingly worried -- though probably no less so than her agent.
Pocked with plot holes -- Where is Interpol? Whom are the thieves stealing from? -- "Fuze" nevertheless offers useful information to would-be robbers. Such as a hammer is the best way to test a diamond's authenticity, and, if you want to track the transfer of millions of dollars to multiple bank accounts simultaneously, the outdoor Wi-Fi in Istanbul is clearly sensational.