"Hawaii Five-0" returns this Friday to infuse some tropical sunshine into the mainland's brutally cold winter.

On the upcoming episode, "O Kela Me Keia Manawa" ("Now and Then"), McGarrett (Alex O'Loughlin) will help Captain Grover (Chi McBride) search for a friend who has disappeared after it appears like he committed murder. 

Also, Kono (Grace Park) will continue in her search to find Adam (Ian Anthony Dale), then will finally return home to Hawaii.

On the last episode of the season, called "Pukana" ("Keepsake"), Chin (Daniel Dae Kim) was kidnapped by a sadistic serial killer, and Danny helped a father find a reconnection to his late daughter.

In the episode, the team finds the body of a burglar in a car, which leads them to a serial killer. Chin goes to a house looking for the suspect, and a seemingly normal man opens the door. However, he proceeds to tie Chin up and throw him in his basement. Afterwards, the man's girlfriend shows up, so he ties her up and throws her in the basement along with Chin. 

After the team realizes that Chin is missing, they immediately begin a search for him. But in the end, Chin is able to save himself; he kills the man before the team bursts into the basement.

Meanwhile, Grace (Teilor Grubbs) finds a box on the beach, and Danny (Scott Caan) tries to figure out what it means. It turns out that it came to Hawaii from a Japanese tsunami years ago.

Danny and Grace then fly to Japan to return the box to the father of the deceased daughter to whom it belonged. 

The next episode, "O Kela Me Keia Manawa," airs Friday, Jan. 10 at 9 p.m. on CBS.

Watch the promo for the upcoming episode below.