Paramount+ is a great streaming service for building your next movie marathon. It adds dozens of movies at the beginning of each month. It added 82 new movies and shows this May alone . Plus, it adds new movies from Paramount Skydance studios on an ongoing basis, a few of which I'll discuss momentarily. So with all these newly added movies to choose from, it can be tough to know which movie to start with. The good news for you is that I've looked through the full list, and I've found the three movies you need to watch first this weekend. There's a pair of new horror movies you'll want to check out first. "Scream 7" is the latest installment in the slasher franchise and one of the biggest movies of the year, and "Slanted" is a body horror flick with a premise you won't see coming. Finally, if you like to watch Jason Statham beat up people, "The Mechanic" is a newly added movie you'll want to add to your watchlist. Here are the three new to Paramount+ movies that you need to be streaming this weekend.…