LOS ANGELES, April 14 (UPI) — Four sequels to the 2009 Sam Worthington-Zoe Saldana blockbuster Avatar are now in the works, director-producer James Cameron announced at 20th Century Fox’s CinemaCon presentation Thursday.

“We’ve begun to bump up against the limitations of our art form,” Entertainment Weekly quoted Cameron as saying. “There’s just too much story.”

The Titanic and The Terminator filmmaker said fresh installments in the Avatar sci-fi franchise will hit theaters on Christmas in 2018, 2020, 2022 and 2023.

“Each one of which stands alone, but which together form a complete saga,” Cameron explained.