Joaquin Phoenix's next project appears to be Ari Aster's follow up to Midsommar, the surrealist horror Beau is Afraid.
The synopsis: An anxious man learns of the death of his mother under mysterious circumstances and upon traveling home makes an alarming discovery about his past. During his journey, he runs into various crazy supernatural threats.
The film appears to be based on Aster's short film "Beau." The script has also already leaked.