'Hawaii Five-0' Series Finale: McGarrett and the Team Race to Save Danny in Tense Sneak Peek (Exclusive)

Five-0's last mission is an important one.

Hawaii Five-0's last mission is a big one.

On Friday's series finale of CBS' long-running action drama, Steve McGarrett (Alex O'Loughlin) and the Five-0 team are faced with their most daunting task yet when Danny "Danno" Williams (Scott Caan) is abducted and badly wounded by someone (see: Wo Fat's wife) who's also after the cypher left by Steve's late mother for him to solve.

In ET's exclusive sneak peek from the episode, titled "Aloha," McGarrett and the Task Force desperately race against the clock to try and find any lead on the motivations behind Danny's kidnapping and where he could be. 

"Whoever took Danny wanted to keep him alive," Grover (Chi McBride) astutely observes, "so until we find hard evidence to the contrary, we're going to treat this like a kidnapping. Nothing more."

Seconds later, MacGyver's Lincoln Cole (Lance Gross) bursts into the room along with McGarrett, who update the team on Hawaii P.D. joining the search.

It doesn't take long for the team to scrub through footage from Danny's abduction in the middle of a busy intersection and reality begins to set in that this isn't like any other case. Watch ET's exclusive clip above to see what happens next.

ET spoke with showrunner Peter Lenkov about why it was time for Hawaii Five-0 to end after 10 seasons.

"Honestly, I think every season I go into it thinking that it possibly could be the last season. And Season 10, it felt right to everybody," Lenkov said. "Alex, Scott, the actors, everybody at the network just thought, 'OK.' It just felt right. I mean, maybe it's a gut instinct. When the network called, we just felt like it was the right thing to do."

The series finale of Hawaii Five-0 airs Friday, April 3 at 9 p.m. ET/PT on CBS.

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