The tone is all over the place as “The Eternal City” tries to encompass that kind of humor along with zany slapstick, wholesome coming-of-age moments, pleasing travelogue scenery and serious peril. At one point, a teenage boy is being stalked at gunpoint through a field of sunflowers; soon afterward, he’s enjoying a romantic Italian sunset. Coleman and Schaal’s characters get hit and kicked in the face, which feels needlessly brutal. Maybe the logic was that Coleman’s Sophie is 14 now, so viewers will be a few years older, too, and can handle a higher level of intensity. Whatever the reasoning, it feels misguided — and from a broader entertainment perspective, it simply doesn’t work. 

This time, Bautista’s CIA operative JJ is trying to enjoy a quiet life in northern Virginia as a father figure to Sophie, who’s a high school freshman, while Sophie’s ER nurse mom is conveniently traveling for work. (There’s a ton of clunky exposition off the top explaining what these characters are doing these days: “I’m just glad the CIA gave you some time off.” That sort of thing.) JJ is done killing people. He makes scones now. So when he gets the opportunity to chaperone Sophie’s school choir on a trip to Italy, he figures his globetrotting skills will make it super easy. But teenagers — they’re challenging! Plus, there happens to be a plot involving hidden nukes that he has to stop in the process. 

Naturally, Sophie gets sucked in, which makes it tricky to pine for the jock she has a crush on (Billy Barratt). Meanwhile, her best friend Collin (Taeho K), who secretly has a crush on her, also is along for the school trip. It’s that classic John Hughes movie scenario where the right one was there all along, only these characters aren’t developed well enough to make you care whether she ends up with either of them in the end. 

Schaal’s tech-wiz Bobbi also travels to Italy to help foil the villain’s plan to blow up the Vatican, and eventually JJ’s boss (Ken Jeong) gets dragged in, too. New additions to the cast include Anna Faris, who’s unrecognizable at first as a brunette, and Craig Robinson, who doesn’t get to do much until the closing credits. Whatever comic gems you’re expecting from a cast like this never truly emerge; there’s too much going on, as “The Eternal City” lumbers from broad violence to treacly sentimentality. 

When “The Eternal City” does take a moment to settle down, Bautista and Coleman do still enjoy a pleasing back-and-forth with each other. He’s a big guy with a light touch for comedy; she’s poised beyond her years without being precocious. And anyone who’s dealt with a teenager can relate to the baffling surliness that emerges out of nowhere — but like needless sequels, this, too, shall pass. 

On Prime Video now.