HBO’s The Last of Us series may be so big that it requires four seasons to tell the whole story.

Speaking to Deadline recently, series co-creator and co-showrunner Craig Mazin opened up about the upcoming second season of the series. With Season 2 set to run for seven episodes and Season 3 also rumored to be “significantly larger,” Mazin said that a fourth season may be necessary.

“We don’t think that we’re going to be able to tell the story even within two seasons [2 and 3] because we’re taking our time and go down interesting pathways which we did a little bit in Season 1 too,” Mazin said. “We feel like it’s almost assuredly going to be the case that — as long as people keep watching and we can keep making more television — Season 3 will be significantly larger. And indeed, the story may require Season 4.”

Mazin doubles down on The Last of Us Season 4

Elsewhere in his talk with Deadline, Mazin seemed to definitively state that a fourth season of The Last of Us would be necessary.

“One thing is absolutely for sure, I don’t see how we could tell the story that remains after Season 2 is complete in one more season,” said Mazin.

Mazin also hinted that Season 2 and any future season would also feature stories that might not necessarily have been given a lot of time in The Last of Us Part II. The first season of The Last of Us also explored this, most notably in the critically acclaimed third episode “Long, Long Time.”

The Last of Us Season 2 stars Pedro Pascal as Joel Miller, Bella Ramsey as Ellie, Gabriel Luna as Tommy, Kaitlyn Dever as Abby, Young Mazino as Jesse, Isabela Merced as Dina, Danny Ramirez as Manny, Ariela Barer as Mel, Tati Gabrielle as Nora, Spencer Lord as Owen, Jeffrey Wright as Isaac Dixon, and Catherine O’Hara in an undisclosed role.

A premiere date has not yet been set for The Last of Us Season 2.