Diahnna Nicole Baxter

Agent Matt Simmons joins the BAU team in a race to take down Mr. Scratch and save one of their own in the process.

The Governor calls on Team Scorpion when his daughter is mysteriously "bio-hacked" with a deadly virus and has only 24 hours to live. Meanwhile, the case takes on a deeper significance for Walter after he receives a letter regarding his sister.

To rescue Joelle from further torture by the Russians, Callen and NCIS must offer up Anna as bait to Katya.