If Morgan is Kidnapped:

Level-headed Karadec losing every last bit of calm and control as he becomes desperate to find her.

Morgan being called Karadec's "weakness"/Karadec being told caring for Morgan makes him "vulnerable".

Karadec immediately developing the world's largest guilt complex bc protecting Morgan is HIS responsibility. Bonus if the kidnapper is someone from Karadec's past seeking revenge, who purposefully targeted Morgan to hurt him.

If Karadec is Kidnapped:

Oh, you thought Morgan was chaotic BEFORE? Now she's essentially a hurricane compressed into a laser, pointed at one thing only - getting Karadec back. She is going to hit you harder than anything you ever thought possible (figuratively and literally).

Soto sending Morgan home (with police protection) bc she doesn't want Morgan to get kidnapped too. so Morgan privately investigates Karadec's disappearance, without the police knowing.

Morgan figuring out where Karadec is, arriving first on the scene, and refusing to wait for back-up before running in to try and save Karadec.

Bonus Tropes for Either Scenario:

Being used as bait to lure in the other. And the other knowing they're walking into a trap but doing it anyway.

Kidnapper massively underestimating Morgan, whether she's the hostage or the rescuer. The kidnapper thinks she's just Karadec's pretty partner that occasionally makes observations or spouts facts, rather than seeing the fully intelligent, cunning, and tough as nails person she is.

The person kidnapped being certain their partner will find them.