James Cameron has officially begun production on his four Avatar sequels, which are completely real and not the deranged delusion of an out-of-control egomaniac. According to Deadline Hollywood, James Cameron and his entirely nonimaginary crew got things underway in Manhattan Beach, California, Tuesday, setting in motion a projected four movies with a combined budget of more than $1 billion, to be shot sequentially and in 3-D, and released beginning Dec. 18, 2020. (It says something that the fact that the sequels reportedly feature roles for Sigourney Weaver and Stephen Lang, both of whose characters were killed in the first film, is far from the craziest thing about them.) The official Slate position that betting against James Cameron is never a wise move remains unchanged, as does our enthusiasm for seeing the Avatar sequels when they are eventually completed. But it’s probably not a good idea to lock down your weekend plans for December of 2020 just yet. Just count on your great-grandchildren having something amazing to watch one day.