Seen Some Pretty Dumb Thriller Premises, But This One Takes the Gold

If there's one thing I can't stand it's a story where one phone call to the cops would make the whole movie go away.

After a number of obnoxious, unstable strangers are led through the front door by her husband, J Law's husband explains, "They have no place else to go, so I said they could stay here and invite some friends."

Yes.
He really says that.

A more honest line from the screenwriter might be, "I was too lazy to think up a situation that could actually occur on planet earth, so instead I made up this ridiculous one that works in my deranged head."

I didn't like this movie right off, starting with the husband being old enough to be our hero's grandpa. Seeing his manner and reactions, it's clear he's up to something and it's nothing good. Or I could have saved myself the trouble and just noticed he's Xavier Bardem.

"They have no place else to go."

This is a typical statement you might hear from a politician.
Let's break it down:

1) Blanket statement of fact with no evidence offered.
Because they told you and you believed them?
Maybe you hired a team of researchers, and after tirelessly scouring the area for days found that there is, in fact, not a single other place for them?

2) Given that #1 is true, they must therefore stay with us, in our house, regardless of how that might cost or endanger us.

Statement #1 is designed to shut down any discussion. Once you accept that (and you've been given no reason to), it's assumed you'll make the leap to accepting #2. You're not supposed to notice that even if #1 is fact (and we are a long way from that), #2 still doesn't necessarily follow at all.

"911 -- what is your emergency?"

"My husband let a bunch of crazy violent assholes into my house and I don't feel safe. One of them assaulted another. I've asked them to leave but they won't."

A police car will show up.
The crazies will leave.
A report will be taken.
That is all.

This is a stupid premise, a stupid movie, and a stupid waste of millions and the talents of JL and others.