Imagine a world overrun by Zombies. What? Again!?

This review, by conscious intention, will refrain from mentioning the words “George Romero” (and any of his — or anyone else’s — “Living Dead” movies), “zombie apocalypse”, “The Walking Dead” or any of the parodist (and one romantic) undead-come-alive movies.

The reasoning behind this is simple; “World War Z”, which bases itself on the most elementary of this genre-specific premise — and the 2006 novel by MaxBrooks — is trying its best to step away from conventions, while staying within convention.

So, of course there are easily angered, always cannibalistic and ravening masses of infected folks attacking populaces; And of course, they make strange, crackling noises and crack their jaws as if they have severe problems in their dentures; And perhaps we find ourselves associating with a lonesome individual making headway out of this unwarranted mess. Every one of these preconditions comes with the territory.

The departure then, is the able-handed handling of the material by director Marc Forster (Finding Neverland, The Kite Runner, Quantum of Solace), and the four credited screenwriters Matthew Michael Carnahan, Drew Goddard, J. Michael Straczynski, Damon Lindelof — the writers whose individual filmography include Lions for Lambs, The Cabin in the Woods, Underworld: Awakening and Prometheus. This curious assortment of talent is a worthwhile mix that has Z walking the line between a barbaric, bombastic blockbuster and a soft-cored daddy in distress movie.

Brad Pitt plays Gerry Lane — the daddy — a former United Nations employee whose family includes a wife (Mireille Enos) and a set of kids (Abigail Hargrove, Sterling Jerins). The family on its way to the children’s school gets locked in a traffic jam when the zombies attack. Here Mr. Forster’s camera (whose chores for cinematography fall to Ben Seresin), slows down a beat amidst the chaos for Gerry to register that it takes 10 seconds for a man-to-zombie transformation. There is another moment like this in Z later, and — although lingering on sterility once past this part —this slight sublimity is just one of the reasons why the movie works as well as it does.

Ok. So it does get silly at one point, especially when Gerry becomes an investigator on government pressure and globe trots from South Korea to Jerusalem to Cardiff, Wales, triggering — more or less —a pandemic wherever his feet touch. While there is no possible cure for the billion and climbing infected — or signs of how it originated — but for all intents and purposes, Gerry’s arrival corresponds to bad luck for anyone living in the locality (even the airways, and a Spanish family aren’t safe from his influence).

Mr. Pitt plays the affected with unpretentious despondency, with his usual supporting side-characters — the in-role beard and overgrown hair. Ms. Enos has a handle on Gerry’s military-ship bound wife, kept for safekeeping by Gerry’s friend Thierry (Fana Mokoena), the UN Deputy Secretary-General. Z also features, if briefly, James Badge Dale, Ludi Boeken, Peter Capaldi, Pierfrancesco Favino, Ruth Negga and Moritz Bleibtreu — each limited to his or her geography. By far Mr. Pitt’s longest on-screen action compadre is Daniella Kertesz, a tough as nails Israeli soldier who gets her arm chopped off by Gerry for a legitimate reason.

At times, it seems Gerry is perhaps the only commonsensical guy in the world, piecing together clues in an insane, fussed, dreadlocked world. But then again, Gerry’s the hero. As it usually happens in insane worlds (andbox office predicted smashes)it’s the hero who saves the day — no matter how pedestrian he wants himself to be.

World War Z” stars: Brad Pitt, Mireille Enos, James Badge Dale, Daniella Kertesz, Matthew Fox, David Morse, Fana Mokoena, Abigail Hargrove, Sterling Jerins, Fabrizio Zacharee Guido, Ludi Boeken, Peter Capaldi, Ruth Negga and Moritz Bleibtreu.

Directed by Marc Forster; Written by Matthew Michael Carnahan, J. Michael Straczynski, Drew Goddard and Damon Lindelof (based on Max Brooks’ novel “World War Z: An Oral History of the Zombie War”); Produced by Brad Pitt, Dede Gardner, Jeremy Kleiner and Ian Bryce. With Cinematography by Ben Seresin; Editing by Roger Barton and Matt Chessé and Music by Marco Beltrami.

Released by Footprint Entertainment and Paramount, it is rated PG-13. Parents cautioned: the film (and a decent number of its special effects, including fake zombies) look better in 2D.