Kono's fears that Adam's past will come to haunt them will finally come to fruition on Hawaii Five-0.

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The former Yakuza member on the Five-0 investigator are happily engaged in paradise, but it seems Adam Noshimuri (Ian Anthony Dale) won't be able to outrun his family's legacy forever.

"Wo Fat was a thorn in their side, [but] Wo Fat was one of the knowns," actress Grace Park (Kono) warned TV Guide. "There are so many things that are unknown that could pop up. ... There continues to be ghosts rising out of Adam's past, and... they do nip at their relationship."

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That does not bode well for the pairs impending nuptials.

Kono, meanwhile, will have her own personal problems to deal with before season 5 comes to an end. Viewers will get to flashback to a very young Kono as she learns to surf, meeting her parents in the process. The flashback will come as the cop finds her herself trapped at sea as a storm rages around her during episode 23.

Find out more when Hawaii Five-0 airs Fridays at 9 p.m. ET on CBS. Click the video below to see a preview for the series' next episode.

Tags: Hawaii Five-O television CBS