I think this might be my favorite Moomin book so far. It's the fourth I've read. It's midsummer in Moomin Valley and Snuffkin has yet to return from his winter adventures. Moomintroll is missing him terribly. But, the local volcano erupts and causes a stir in the ground, or something, which causes the sea to rise and engulf the Moomin house. About the time the water gets up to the roof, a sort of cave floats by and they all jump into it. It's a strange cave, with red velvet curtains, lots of nice pictures in the rafters, and rows of lights along the open side, the one with the red curtains. There's also someone who cackles in the night. Eventually, they find it's a theater in which they're living and the cackling comes from a properties mistress (or something). They decide to put on a play, which Moominpappa has chosen to write. But different people want different things, so Moominpappa keeps having to revise his script. In the meantime, Moomintroll and the Snork Maiden have been arrested for destruction of property. The actual destruction was done by Snuffkin, who was on his way back to Moomin Valley from his adventures. Along the way, he found Little My floating on the ocean, and has picked up some 24 Woodie children. Being a father is tough on a born wanderer. Anyway, somehow they all end up at the play, escape from the Hemulic police and make their way back to Moomin Valley and back to the Moomin house. They have to fix quite a bit up, but it's always good to be home.
The above is undoubtedly garbled and misses out on some delightful new characters, The Whomper and Misabel. Anyway, it was a rather charming story, which is just what is needed in to distract our minds from all the cruelty now being imposed by our brand-new, kleptocratic government. As Jimmy Buffet would have it, "if we couldn't laugh, we would all go insane". The Moomins keep us grounded, keep us laughing, and keep us from going insane. Bless their hearts.