Harry Ambrose may be retired but the mysteries keep piling up.

This week, the trailer was released for season 4 of “The Sinner”, which sends Bill Pullman’s character to Maine for a new investigation.

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“Still reeling from the trauma of a previous case a year ago, the now-retired Harry Ambrose (Bill Pullman) travels to Hanover Island in northern Maine for a recuperative getaway with his partner Sonya (Jessica Hecht),” the description reads.

“But when an unexpected tragedy occurs involving Percy Muldoon (‘Orange Is the New Black’‘s Alice Kremelberg), the daughter of a prominent island family, Ambrose is recruited to help the investigation, only to be thrown into a mystery of mounting paranoia that will turn this sleepy tourist island, and Ambrose’s life, upside down.”

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The new season also stars Frances Fisher, Neal Huff, Cindy Cheung, Ronin Wong, and Michael Mosley.

“The Sinner” season 4 premieres Oct. 13.