Boasting topical subject matter but the vibe of a middling 1950s sitcom, “Playing With Fire” stars John Cena as the head of a team of wildfire-fighting smoke jumpers tasked with baby-sitting — even though, get this, they’re all men!

Keegan-Michael Key and John Leguizamo ham it up as panicky sidekicks to Cena’s workaholic Jake, who takes in three children (Brianna Hildebrand, Christian Convery and Finley Rose Slater) whose parents are absent, after extinguishing a blaze at their cabin.

Director Andy Fickman (“Paul Blart: Mall Cop 2”) favors poop jokes and the cringe-humor of watching little kids court danger with a nail gun, kerosene, an ax and sometimes literally fire. Hildebrand, a 20-something playing a teen, seems unenthused. Likewise, Judy Greer is low-energy as Cena’s biologist love interest, who’s repeatedly assured she’s not being dragged in to help just “because you’re a woman.”

If there was a single female name in the writing or producing credits, I’d be more inclined to buy that.