Ahead on the series premiere, Hulu’s Castle Rock creators Sam Shaw and Dustin Thomason made a stop to Austin’s ATX Television Festival. During the conversation following an exclusive first look clip, it was revealed that Fargo standout Allison Tolman will recur on the series as Melanie Lynskey’s character’s sister.

Thomason shared a cheeky anecdote of Tolman’s serendipitous casting. “When Melanie was cast, there was a casting announcement and Allison saw the announcement and tweeted at Melanie and they did not know each other [at the time]. She tweeted at Melanie and said ‘I’d love to play your sister.'”

“But the weird thing was we knew she had a sister [Allison did not]. But as soon as she said that we thought Allison Tolman would be the perfect sister. It was a little creeping because we had just written the scene.”

From J.J. Abrams and Stephen King, the series is named after the fictional town in King’s native Maine that is featured prominently in a number of his novels, novellas, and short stories. It combines the mythological scale and intimate character storytelling of King’s best-loved works, weaving an epic saga of darkness and light, played out on a few square miles of Maine woodland.

The guys talked about the importance of obtaining King’s approval despite the fact that he has no direct involvement with the series.

“There were early conversations about getting his sanctions and blessing, said Shaw. “The truth is even if Warner Bros controls the rights and said great go ahead, Castle Rock is an important town in the Stephen King library so it was really crucial and we needed and wanted to have his blessing. We were gratified when he said yes.”

Andre Holland, Bill Skarsgård, Sissy Spacek, Jane Levy, Scott Glenn, Terry O’Quinn also star.

Hulu will drop the first three episodes on July 25.