It's funny when you encounter a film with so many likeable elements that simply never cohere into something that works. This film reminded me of "I Heart Huckabees" in that sense ... I enjoyed all the parts considered in isolation, but the film itself is decidedly less than the sum of it's parts.
The film is divided into three acts. We're introduced to star professor of Hitler Studies Adam Driver and his wife Greta Gerwig and their children (almost all from different spouses) in the first act, which gestures at parodying academia without really landing much.
In the middle act, a train crash causes the Airborne Toxic Event ... a cloud of poisonous chemicals that descends on town and causes the family to evacuate. This is the most successful part of the film, impressively staging the event like a darkly comedic disaster film.
The final act is ... a lot less clear and probably best not spoiled. It deals with our need to distract ourselves from the terrors of life with medicine and consumerism. It descends into talky meandering and is really only saved by a magnificent musical number over the end credits.
There's really a lot to like. I found it to be intermittently quite funny. The performances are great, especially Don Cheadle as a fellow professor trying to establish a specialization in Elvis Studies. It's a hugely ambitious film with a unique visual style. I only wish I could say I actually liked it.