Has it been enough time that we can talk about this? I will still try to avoid spoilers.
Doctor Strange (Benedict Cumberbatch) is feeling a little wistful after seeing the girl he might have loved, Christine (Rachel McAdams), marrying someone else. So when America Chavez (Xochitl Gomez) drops in with the power to traverse the multiverse, well, who wouldn't want to take a peek and see where they might have ended up if they had made a different choice? Wanda Maximoff (Elizabeth Olsen) sure does. Wanda has not forgiven or forgotten that she was forced to give up her sons, and with the power of the Darkhold, she can steal enough of America's power to travel to a timeline where she's still a mother and damn the consequences.
There are major cameos that are literally spoiled on the IMDb page but I will not list them here. Instead, I'm going to talk about how Sam Raimi brought horror into the MCU. And this is a horror movie. It is Evil Dead Lite, complete with Bruce Campbell. There are a few really gory moments and at least one jump scare. If Moon Knight was too much for you, go ahead and steer clear of Multiverse of Madness. If you are a gorehound for whom too much fake blood is never enough, this will feel like a no-calorie dessert. But there is a sweet spot in the middle for people who have been getting a little tired of how nice the MCU is and want to see more of a darker edge. It's probably not suitable for the youngest members of your house, but older kids (11+) will be okay.
Multiverse of Madness is currently only showing in theaters but it'll move to Disney+ in a couple of months.