Hawaii Five-0 is back in action.

'Hawaii Five-0' Season 6: Kono & Adam's Take 'Worst Honeymoon' Ever, EP Teases Premiere Problems

The CBS series is gearing up for season 6, and that means scripts will be coming in fast and thick as the start of filming draws near. To make sure the actors have lines to say this summer, the series' writers room jumped back into action on Monday.

"Day 1 of #H50 season 6 is in the books," Steve Lillian, the scribe behind the season 5 finale teleplay, tweeted at the start of June. "And I know what ur asking. Will the season premiere be awesome? Answer: it most certainly will be!"

'Hawaii Five-0' Season 6: How Long Will Catherine Stay? EP Teases McRollins Future

Showrunner Peter Lenkov confirmed the start of pre-production, posting a photo of his notes on the characters' upcoming storylines (see below).

"A Make Kaua (Until We Die)" threw viewers into the summer hiatus with several cliffhangers. When the fall premiere opens, Kono (Grace Park) and Adam's (Ian Anthony Dale) wedding reception will be in full swing, Gabriel Waincroft (Christopher Sean) will be poised to become the next Wo Fat, Steve (Alex O'Loughlin) will have to figure out his relationship with the newly returned Catherine Rollins (Michelle Borth), and Danny (Scott Caan) will be ready to fight for his son's life.

"[Gabriel is] definitely going to be a force to be reckoned with, and he's going to come right up, very hot out of the gate in the first episode next season," Lenkov informed The Hollywood Reporter, informing fans that the show will soon reveal the reasons behind Gabriel's continued presence on the island. "Somebody like that, you imagine as soon as he got away, he would have left the island, but he didn't, so you've got to ask yourself why."

Find out more when Hawaii Five-0 head back to paradise this fall on CBS. Click the video below to see a preview for the series' latest episode.

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