Three stars

A family film that mixes explosive action with comedic character development, My Spy is another vehicle to match beefcake with cute kid. This time around it's former Wrestlemania legend Dave Bautista (Guardians of the Galaxy, Stuber) as the man who has to find a soft centre underneath the pecs of steel.

Bautista plays JJ, a CIA agent who has been relegated from handling the explosive dangers of fieldwork with terrorists to watching over a single mother and her daughter in the suburbs. For a take-no-prisoners tough guy who has one last chance to redeem himself for the Agency, observing the daily life of Kate (Parisa Fitz-Henley) and nine-year-old Sophie (Chloe Coleman) seems like dull punishment. It's made worse for him when he's assigned a nerdy tech-partner, Bobbi (comedian and voice-actress Kristen Schaal), who has watched JJ's career from the safety of her office cubicle. A fangirl, she wants nothing more than a little acknowledgment from her hero, and for him to share his knowledge of the dangerous tricks of the trade. He just finds her annoying.

Undaunted, Bobbi sets up all the gadgets needed for the subtle art of surveillance but, when the bumbling JJ is caught out by curious Sophie, the young girl forces him to strike a deal: he will teach her how to be a spy and she won't blow his cover. Of course, the journey for JJ involves understanding Sophie's world of playgrounds and school-bullies, along with the possibility of a romance with Sophie's mum.

It seems to be a career requirement that body builders become babysitters as their movie careers get underway. Back in 1990, Arnold Schwarzenegger went undercover in Kindergarten Cop and, since then, we have seen Hulk Hogan as Mr. Nanny, Vin Diesel as The Pacifier and Dwayne "The Rock" Johnson as the Tooth Fairy. Last month, in Playing with Fire, even wrestler John Cena trod the path. What's fascinating about this sub-genre is that the power dynamic in the parent-child relationship gets inverted, and it's no exception here. It's nine-year-old Sophie who is sophisticated, smart and articulate; always ready to correct JJ when he messes up and point out his flaws in public. By contrast, he's the child: making mistakes, being caught in embarrassing situations and learning how to deal with the emotional side of life.

The success of these films depends on how well the muscleman-turned-actor can handle those carefully plotted moments of cringe-worthy embarrassment. Schwarzenegger excels because he never takes himself seriously, while the Rock just oozes charisma and charm. Like John Cena, Bautista opts for an earnestness that makes it hard not to squirm at times but, as the story plays out and the chemistry between he and Coleman kicks in, the film delivers on its ambition. Schaal's infectious comic timing certainly helps, and it's only the action sequences that let the storytelling down. I watched an early PG-rated version of the film some months ago and felt that the scenes of explosive carnage were fighting against the charm that had been established for a family audience. The new M rating will help soften some of this tension.

The film is directed by Peter Segal, who has had success with comedies like Anger Management and Get Smart, and it's written by Erich and Jon Hoeber, who also penned the spy comedies RED and RED 2. Put this in a similar category: an enjoyable spy spoof, with the film's opening set up and ambitious finale never as convincing or satisfying as the playful fish-out-of-water shenanigans of the middle act.