Hawaii Five-0's McGarrett and Danno will be plagued by past relationships when the CBS drama returns for season 5.

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Over the last four seasons, numerous people have walked out of Steve McGarrett (Alex O'Loughlin) and Danny Williams' (Scott Caan) lives. While McGarrett attempts to deal with Catherine Rollins' (Michelle Borth) sudden decision to stay in Afghanistan, Danny's brother will find his way back into the detective's world.

"We're still breaking story for the season, but a couple places we know want to go this season are McGarrett dealing with Catherine's choice to track down Najib from "Makani ʻOlu a Holo Mālie" ("Fair Winds and Following Seas") will be addressed in the early episodes," said executive producer Peter Lenkov, according to the Honolulu Pulse. "We're going to pick up on the whereabouts of Danny's brother Matt."

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Although it appears McGarrett will soon move on from Catherine when a new love interest enters the scene, less in known about Matt Williams (Dane Cook) return.

The younger brother of Detective Williams, Matt found himself in hot water with the FBI during season 1. When the feds pursued him for money fraud related to his job as a stockbroker, Matt fled to Hawaii and then went on the lam somewhere in Asia.

Find out more about the McGarrett/Rollins drama and Matt's reemergence when Hawaii Five-0 returns to CBS on Sept. 26 at 9 p.m. ET. Click the video below to see a preview of the series latest episode.

Tags: Hawaii Five-O television CBS