NCIS season 21 finale explained: What happened in Reef Madness?

WARNING: This article contains spoilers for the NCIS season 21 finale.

NCIS’ season 21 finale was expectedly gripping with a cliffhanger that could see the end of Jimmy Palmer and Jessica Knight.

The CBS police procedural returned for its latest outing in February and sadly, thanks to the 2023 Hollywood strikes, was the shortest series ever, concluding on Monday, May 6.

With plenty to keep viewers talking until the drama returns for season 22, Express.co.uk has a rundown of exactly what went on in that crucial final episode.

How did NCIS’ season 21 finale end? 

This week’s case kicked off after NCIS was watching the news, where a reporter was given a tour around the decommissioned USS Goddell.

The ship was being given a hero’s burial at sea so it could become a habitat for aquatic species but it was during the live show that they stumbled across three plastic-wrapped bodies.

Read more: NCIS fans eager to know if Agent Knight is leaving after season 21 finale

Before the team got to work, Director Leon Vance (played by Rocky Carroll) pulled Agent Jessica Knight (Katrina Law) to the side to offer her a new job: REACT’s chief training officer at Camp Pendleton in southern California.

Unsure of what to do, Vance said he would give her until the end of the day to make up her mind about the role.

Timing couldn’t have been worse as chief medical examiner Jimmy Palmer (Brian Dietzen) came in flustered after a rough morning as a single parent of a teenage girl.

As a result, he was snappy with Knight as she tried to help him with something with the rest of the team jokingly calling her “chief”, making him aware of the job offer.

Before any more is said, the identities of two of the three victims are revealed: Thomas Mackin was a construction worker who was killed by blunt-force trauma while teacher Susan Sidor was stabbed to death.

Whereas the third victim, currently a John Doe, died after he was hit by a car.

The team is ready to get going to find out more about the victims and head to the USS Goddell when Jimmy pauses to have a word with Knight.

He states that he has lost too much over the years, his late wife Breena Palmer (Michelle Pierce), Agent Gibbs (Mark Harmon), Ducky Mallard (David McCallum) and now his daughter Victoria Palmer (Elle Graper) is growing up.

Rather than try a long-distance relationship, Jimmy insists that she should take the job and “just go” as that’s what would be best.

Of course, the rest of the team are waiting for them in the lift and overhears everything, making the situation even more awkward.

Knight and Agent Alden Parker (Gary Cole) go on board the USS Goddell where they collect evidence in the shape of a broken unisex watch when someone on the ship locks them inside.

To make matters worse, their phones don’t work on the ship that is set to be blown up tomorrow and during the pursuit, Parker’s leg was struck with a heavy piece of equipment, leaving him unable to move.

Elsewhere, Agents Timothy McGee (Sean Murray) and Nick Torres (Wilmer Valderrama) visit the late Tommy Mackin’s wife Molly (Gabriella Piazza) who says the only person who may have wanted to hurt him was his bookie and food truck owner, Sloppy Joe Sammy (Adam Ferrara).

Unfortunately for Sammy, his initial reaction to laugh at the news of Tommy’s death since he was in the middle of selling his truck to cover his gambling debts, didn’t do him any favours.

Back on the boat, Knight manages to pull off the heavy item from Parker’s leg but he is looking pale and in need of medical assistance.

As he loses a lot of blood, Knight ties her belt around the wound and moves her attention to the hatch on the floor, struggling to wedge it open, much to both of their dismay.

Having taken some time away from Knight and with a word of warning from Kasie Hines (Diona Reasonover), Jimmy frantically tries to call his girlfriend to apologise.

Of course, there is no signal on the ship with the team unable to get hold of Parker either, making them all more concerned for their welfare.

When McGee, Torres and now Palmer go to the victim Susan’s house, they not only find the murder weapons which had been recently cleaned, but a picture of herself with fellow victim Tommy.

Kasie also traces Knight’s car to Sammy’s house but as he scoffs at the idea that he’d be so stupid as to leave the vehicle at his home, they start to believe it’s a setup.

The agents turn their attention once again to Tommy’s wife Molly who clearly had a motive to kill both Tommy and Susan, if they were having an affair.

When they try to question her again, Molly is attempting to flee with Lacey from the dock who turns out to be her uncle, explaining how she got access to the ship.

He admits that it was Molly who killed them and that the third victim was a man called Cedric who she hit with her car while trying to dispose of the bodies.

Lacey says he wanted to go back on board to get his watch that he dropped, which is when the team realises that this is where Knight and Parker are.

Parker is barely conscious and begins to hallucinate of a little girl called Lily running around the engine room.

Concerned, Knight manages to open up the hatch, filled with water and tie a rope around the pair of them in a bid to pull them to safety.

Parker begins to envision his sister Lily, this time sat on a ship’s deck, with their mum warning the pair to be careful.

The moment then switches to Knight’s horrific real-life ordeal when she desperately swims, pulling Parker along by the rope until eventually, they reach safety, with the team standing by to help.

Parker is then seen lying in a hospital bed as he begins to recover when Vance approaches Knight.

He questions her about the job opening again but this time she is certain of her decision: “Hell yeah, sir. Let’s do it.”

NCIS is available to watch on CBS and Disney+.