There's a trailer out for a new science fiction film called Moonfall, to be released in early 2022, in which the moon is about to crash into Earth. It features several shots of a reddish moon hovering extremely close to the planet, crumbling apart while sucking the oceans toward it, the debris flying into spacecraft and mountains. It doesn't actually show a collision—you know, it’s just a trailer and they don’t want to spoil everything.
This isn’t the first movie to stretch the bounds of believable physics. (Remember Sharknado?) But just because it's science fiction doesn't mean it's totally wrong. That's why I'm here: I'm going to go over the actual physics that would apply if the moon ever got too close to us.
According to the movie’s official IMDB entry, “a mysterious force knocks the moon from its orbit,” precipitating its plunge toward Earth. That’s not a lot to go on. Would there really be a way to make that happen?