I am among the school of thought that if you're going to remake an old story, remake something that wasn't very good in the first place and attempt to give the material some justice. For a moment, I thought Eli Roth's Knock Knock (2015) could be a decent update to 1977's, Death Game. I was wrong. This is a case of a terrible movie being remade into a modern terrible movie -in some ways, it's actually worse.
If not for the scene in Act 3 when Keanu Reeves has his Cage-esque "not the bees!" moment ("It was free f#### pizza!") there wouldn't be a single redeeming quality. The logic is absurd; the family (especially the wife) is not believable; and the main character is just plain stupid.
Spoilers...
I'm not sure how I feel about the ending, specifically the lack of payoff (Death Game had a nonsense payoff). On one hand, it was irritating that the villains totally got away with it all without any comeuppance, but on the other hand, not everything has to have a happy ending and it's ok that the victim is a male for a change and that the females get away with their villainy. Plus, it was Keanu, so it was hard to feel sorry for him in any way. Had it been a more likeable main (who actually does a single smart thing), part of me would have liked to have seen him have a moment where he turns the tide/tables and gets some payback (yet still have an ending where the girls "win" and get away with it).
Basically, the main comes across as stupid, weak, ineffectual, and a loser who couldn't fight back. Even if this character deserves his fate, it still doesn't make this a good film.
I give it 1 out of 5 free f##### pizzas.
It's too bad because the story premise/concept had potential.