We've been on the record from the get-go that a Joker origins movie is a terrible idea, and that the mere idea that Warner Bros. are seriously trying to float is indicative of the state of things with the DCEU at large.
One of the names who's been attached to this terrible idea is Joaquin Phoenix, who would invariably play the Clown Prince Of Crime from a script by Todd Phillips with Martin Scorsese - of all people - floating in the background somewhere.
However, in an interview with French outlet AlloCine, it looks like Joaquin Phoenix is pretty perplexed about the whole thing. "What movie about a Joker?... I have no idea what you're talking about..."
Take a look and judge for yourself, but it looks like Joaquin Phoenix has pretty much no clue whatsoever about it all.