'NCIS: Hawai'i' Ends With Unintended Series Finale Cliffhanger: Here’s What Happened

Spoiler alert: If you haven't watched Monday's series finale of NCIS: Hawai'i, proceed with caution. 

Monday night marked the unexpected ending to NCIS: Hawai'i after three seasons. After the show was cancelled by CBS last month, viewers watched the cliffhanger conclusion to the series in Monday's finale, titled, "Divided We Conquer." 

The procedural starring Vanessa Lachey as Jane Tennant and Alex Tarrant as Kai Holman, was a part of the successful NCIS franchise, which boasts a variety of spin-offs. 

So how did NCIS: Hawai'i end? The team, including Jane (Lachey), Jesse Boone (Noah Mills), and Sam Hanna (LL Cool J), manage to thwart several attempts from Dr. Annalise Cruz (Rachel Mars) to use the Compound X bioweapon. 

And though Sam (LL Cool J) is exposed to Compound X and has to sit out some of the action to recover, he ends up saving the day, shooting Dr. Cruz in the head while she's holding Carla Chase (Seana Kofoed) at knifepoint. 

The group then enjoys a surprise party for Sam to celebrate complete with some poignant speeches. But that's not how the episode ends. The previously-teased cliffhanger comes when Jane (Lachey) heads home expecting to find her daughter, Julie (Mahina Napoleon). But waiting for her is Maggie Shaw (Julie White). Maggie was last featured on the show in the season 2 finale while on the run. 

"You're probably going to need a drink for what's coming next," Maggie tells Jane before the show cuts out. 

The cast has already spoken out about their disappointment from the show's unexpected cancellation. 

Earlier this month, Lachey posted a video of herself in a beautiful filming location in Hawaii, writing, "I wish we had more time, I'm sorry we don't. I wish we had a proper good-bye, I'm sorry we didn't," she added. "I know we ALL are connected deeper than any TV show. I will go to the ends of the earth for my cast & crew! If you come across ANY of them… hire them! You won't be disappointed. Salt of the earth people!"

NCIS: Hawai'i was the fourth spin-off for the NCIS franchise -- the New Orleans and Los Angeles versions ended in 2021 and 2023, respectively -- and the first with a woman at its forefront. 

As a whole, though, the franchise is a successful one. NCIS and NCIS: Sydney have both been renewed, for their 22nd and 2nd seasons, respectively. There's also a spinoff in the works at Paramount+, which will see Cote de Pablo and Michael Weatherly reprise their fan-favorite roles as Ziva David and Tony DiNozzo.

When ET spoke to Lachey about her role on Hawai'i back in February, she gushed about being "a part of this incredible franchise," which aired its 1,000th episode earlier this moth.

"To be the newcomer -- the baby at three seasons -- and to be able to celebrate 1,000 episodes of a television show, I don't know if people really know how big of a feat that is," Lachey told ET. "... I'm just honored and I'm constantly humbled and I'm very grateful. But I also don't take it for granted."

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