NCIS recap: You need to get gone, girl

Who among us hasn't wanted to stab someone for attempting conversation before morning coffee? The difference is, we probably wouldn't go back to chopping salad with the bloody kitchen shears afterward.

This week's twisty NCIS episode unravels how Lt. Rachel Donohue (Amanda Clayton) ended up attempting to murder her husband, then having no memory of it hours later.

Rachel's an aviation base manager who's been having weird health issues, including clammy skin and headaches. While the team waits for her husband, Logan (Gil McKinney), to wake up from surgery, they question Rachel's doctor. He says her bloodwork was normal but her psych tests were all over the board.

When Torres (Wilmer Valderrama) suggests that she's trying to fake crazy, the doctor correctly points out that "crazy" isn't a diagnosis but confirms that the general suggestion might not be a bad one.

The investigation also uncovers Rachel's recent searches for "how to tell if you're going crazy" and the new credit cards she used to buy outlandish things, including a $500 air fryer and a $5,000 reclaimed wood chair. (Okay, but tell me what that fancy air fryer does for five Benjamins, tho.)

Rachel denies making the purchases and says she and Logan hit a rough patch, but their couples counseling worked wonders. Then her anger toward Logan escalates, and she starts ranting and pacing before passing out in Torres' arms.

As Palmer (Brian Dietzen) checks her out, she claims not to remember what she said in interrogation. But it points the team toward a solution: Rachel's blood has massive amounts of T4, a thyroid hormone that might be causing her symptoms, and it's being delivered via an implant in her arm that Rachel didn't know about. Yiiiiikes.

The only time Rachel's been sedated recently was six weeks ago, when she got a root canal. A visit to Harvey Kimball, DDS, reveals that an anonymous benefactor paid off the good doctor's gambling debts in exchange for him injecting the implant into Rachel's arm while she was under. (He tries to weasel out of trouble by offering free braces for McGee's (Sean Murray) kids, which has to be a little bit tempting, right?)

The implant's technology turns out to be incredibly advanced, with an app-controlled membrane that lets someone dictate when and how much of the drug is released into the bloodstream.

While Torres looks for the mysterious man caught on the Donohues' doorbell cam, Parker (Gary Cole) and McGee head to the biotech startup Dynamical Labs, which holds a patent on part of Rachel's mystery implant.

The CEO's shocked to learn that a shelved prototype ended up in Rachel's arm after the FDA shut it down. And you know who works for the FDA? Logan Donohue. He's the safety officer who pulled the plug on the project and cost 40 Dynamical Labs engineers their jobs, so it's not that surprising when the team discovers he received an emailed threat.

Logan, finally awake post-surgery, blames himself for shutting down the program and says he saw the guy on their security camera drive off in a silver Prius. He also asks to see Rachel. She apologizes, he forgives, and what a wild story those two are going to be able to tell at their 50th-anniversary party.

Kasie (Diona Reasonover), meanwhile, has been going through it this week. She's thrown herself into completing her dream docket list, which includes bringing fancy donuts to work, learning to ride a motorcycle, becoming a chess prodigy (despite the fact that prodigies are generally children), and taking up falconry. Side note: has "dream docket" replaced "bucket list"? Gotta say, I prefer it.

She blows off McGee's concern before confiding in Palmer when her aunt's been diagnosed with early-onset Alzheimer's and she's now waiting to see if she carries the gene for it too. She gets testy with him when he tries to offer her advice, but she eventually turns to Vance (Rocky Carroll), who recently had a health scare.

He tells Kasie that as he was waiting for the test results, he realized that nothing in life is guaranteed, so he started living without regrets every day. (Also, the lymphoma turned out to be benign, so whew for Vance.) Kasie chews on that for a bit.

Back on the case, Parker rolls in with a tray of what are clearly empty coffee cups based on the way he's waving them around and defends McGee, who's being mocked for thinking a Miata's a cool car. McGee then reaffirms his innate coolness by linking a tattoo on one of the engineer's arms with the same logo on the lurker's hoodie. Never wear branded gear to do crime!

The engineer admits that it was him at the Donohues' house but insists he was there to blackmail Logan for stealing the implant prototype, presumably to sell to the competition.

Oh, Logan. I'm not so much surprised as mad and disappointed. Because yep, the shell company that paid the dentist belonged to Logan. Geez, just get a divorce!

Rachel agrees with that assessment and leaves NCIS to grapple with why her husband hated her so much that he started laying the groundwork months ago to have her declared incompetent. As Parker suspected, she heads straight to where Logan's hiding at his grandpa's cabin. She picks up an ax and threatens to kill him — this time without the influence of T4 hormones.

Logan admits that six months ago, he intercepted a letter for Rachel informing her that she'd inherited a $10 million trust fund from a rich cousin, and he hatched his plan to take control of her finances after learning that he wouldn't benefit if they divorced or Rachel died.

The team arrives to arrest him, and Knight (Katrina Law) nods her approval when Rachel says she only threatened Logan with the ax so could secretly record his confession.

In the final scene, Kasie tells Palmer that she no longer wants to find out if she carries the Alzheimer's gene because she wouldn't want that knowledge to change the way she lives. She deletes the email with the results, and she and Palmer settle in for a night of popcorn and video games.

Good for her, but I could never.

Stray shots

• Which is more upsetting, McGee having twice the nerve endings in his mouth, or Torres digging the dental office vibes?
• Those regenerative organs and microbiomechanical systems were so cool. Bring on the minuscule manufactured replacement nerves and lab-grown hearts!
• I would have bet all my money on Torres being the last person to know about the secret progressive history of Monopoly, aka the worst board game.

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