(CNN) Paul Walker's untimely death forced the "Fast & Furious" franchise into a rare moment of sobriety, an interlude that hits the brakes with "The Fate of the Furious." Yet even more free-spirited mayhem doesn't rev up the eighth installment in this hugely lucrative series, specializing in fast cars and artfully blowing stuff up.

At this point, shuffling alliances and adding a few big-name actors (principally Charlize Theron, here as a Bond-esque cyber-villain known as Cipher) is about all that can be done to distinguish one outing from the next, which doesn't prevent the movie from feeling mechanical, and -- at well over two hours -- a little bloated.

With nuclear weapons in the mix, nobody can accuse this latest adventure of playing for small stakes. Still, "Fate of the Furious" (which eschews designating its sequel status numerically, other than its Twitter hashtag) only sporadically sparks to life, with the best recurring bit involving the macho banter between Dwayne Johnson and Jason Statham's characters, which eventually prompts even these tough guys to burst out laughing.

The plot, such as it is, proves almost incidental. After an opening sequence set in Cuba that mostly squanders that locale, the gruff automaton Dom (Vin Diesel) encounters Cipher, who finds a way to coerce him into assisting her.

Having Dom go "rogue," as federal agent Luke Hobbs (Johnson) puts it, throws his team into a tizzy, forcing them into an uneasy alliance with the aforementioned Deckard Shaw (Statham). That leads to a globetrotting quest to thwart Cipher's plans.

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