Rating: ★★★☆☆ (3/5)

There is a moment early in Animals that I couldn’t shake. A little boy heads out trick-or-treating on Halloween night, surrounded by masks and costumes, in a city where nobody looks twice at a stranger in disguise. It’s a clever, unsettling way to open a kidnapping story, and for a while I thought Ben Affleck was about to give Netflix the grown-up thriller it badly needs. He comes close. He just doesn’t get all the way there.

Affleck plays Mark Kimball, a self-funded independent running for mayor of Los Angeles. He’s behind in the polls, his money is almost gone, and his marriage to Abigail (Kerry Washington) is held together mostly by appearances. Then their son is taken, and the ransom is $7 million that Mark simply doesn’t have. What follows is less a race against the clock and more a slow look at what a man becomes when the polished version of himself is no longer useful.

I liked the idea behind the title more than the film itself. Strip away the campaign posters, the donors and the press strategy, and these are people acting on instinct, protecting what’s theirs. That’s a fascinating thing to explore in a story about a politician who sells himself as the reasonable, caring choice. Unfortunately, the movie keeps telling us this instead of letting us feel it.

My biggest frustration was how crowded it is. There’s a campaign, an affair, money trouble, class resentment, a fixer, a ransom drop and a mystery about who is really behind it all. Any two of those would have made a tight, nervy thriller. All of them together in under two hours means each one gets a few scenes and then gets pushed aside. By the final act, I was ahead of the story more often than I wanted to be.

The cast is stronger than the material. Gillian Anderson walks in as Dayle, a woman whose job is to make rich people’s problems disappear, and she plays her with such dry calm that I wished the film followed her instead. Adriana Paz and Luis Gerardo Méndez bring a warmth and pain that feel real, and they quietly carry some of the best scenes. Affleck and Washington are capable, but I never believed these two had shared a life, which matters a lot in a story about a family falling apart. Steven Yeun, as Mark’s campaign manager, deserved a better-written part.

Credit where it’s due: Affleck still frames a scene beautifully. His Los Angeles is all glass houses, empty roads and orange streetlights, a place that looks expensive and feels lonely. When the film slows down and lets the tension sit, it works.

Animals is not a bad movie. It’s a frustrating one, because the pieces of something special are right there on the screen. If you’re in the mood for a dark, adult thriller and you go in with modest expectations, it’s a perfectly decent evening. I just kept waiting for it to bite, and it mostly growled.

The Verdict: A sharp premise and a terrific Gillian Anderson keep Animals afloat, but too many storylines and too few surprises hold Ben Affleck’s thriller back from greatness.

Animals is now streaming on Netflix.