I'm a big fan of Coen Bros. movies, especially the funny ones like Hail, Caesar! (2016). They tend to meander about, with lots of happenings but no real point. I feel like Hail, Caesar! has less plot than most, which is great.
It is about a Hollywood producer/fixer in 1950s Hollywood, Eddie Mannix (Josh Brolin). His job is to find scandals before they happen and squash them, using money or muscle. He's very good at what he does, but he is conflicted. He goes to confession a lot, and also considers an offer to work for security at Boeing - in their nuclear program. What, and give up show business?
One of his responsibilities is Goerge Clooney, who is starring in the titular movie-within-the-movie, Hail, Caesar: A Tale of the Christ. To make a long story short, he is kidnapped by a gang of communist screenwriters and held for ransom. That ransom is a bit of a McGuffin, though. Actually, Clooney kind of likes the commies, and doesn't mind being kidnapped.
Since that isn't the "plot", what is? Well, we get an Esther Williams-style water ballet starring a profane Scarlett Johansson, a hayseed cowboy star being shoehorned into a white-tie drawing room comedy, Tilda Swinton as a pair of twin gossip columnists who hate each other, Channing Tatum doing a sailor musical, and so on. Some people thought the movie parodies were weak - they were just recreations without much point. I thought the point was the recreation. They were probably fun to make and they are fun to look at.
Maybe if I watched this again, I'd see that it is all connected. If not, so what, it's a fun ramble through old Hollywood. It doesn't have the old timey music of O, Brother or the neo-screwball of Intolerable Cruelty, but it's fun. We liked it.