My fiances cats don't get along with her parents cats. They get along fine when there's a door between them but when she took her cats out of the room they were in they started freaking out, hissing, and growling about halfway down the hallway. Does anyone have any ideas how to make them get along?

There's no way to make cats get along at all. Either they will, or they won't.

If you introduced them to each other suddenly they're going to need time to get used to each other. You should keep them separated for now and then give them supervised time together.

Watch animal planets my cat from hell, it's on netflix right now and has many useful suggestions and is interesting ot watch

As said, the program "My cat from hell" has some great tips. Provide a lot of high places, like shelves, so that the cat that is being attacked can get away, and can observe the other cat.

Yeah, you can't really make them get along. Especially if they're adult cats. "My Cat from Hell" may be able to help, but all cats are different and won't react the same way. Good luck.

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