NCIS

This week on NCIS, the team has to find a serial killer, and their investigation leads them to a surprising revelation. Meanwhile, McGee tags along with Abby to Mexico, as teased in last Tuesday's "Obsession," where she has to give a presentation.

The topic of Abbs' speech? Forensics in cold cases. The fact that this takes place in Mexico could foreshadow trouble for a certain agent, given what we know from previous seasons.

Here's a promo of tomorrow night's episode, "Borderland" ...

Clearly, something she turns up pertaining to our man and he's not happy. But what do you think happens between Gibbs and Abby - and how will it escalate in the next few weeks?

Follow the jump for some NCIS pictures from the episode ...