So Gibbs killed Phineas' Mom a couple of seasons ago, because she was the spy that wanted to kill Ziva "The Diva" David. In spite of the fact that Gibbs put a cap in his Mom, little Phineas keeps coming back to Gibbs as some kind of grumpy old grandfather figure.
This time Phineas shows up after his real dad, the international terrorist, tries to kill his foster parents. How did the kid walk across the entire county to find Gibbs without a GPS or cellphone?
The Scooby Doo Crew is behind the curve, like usual, but Gibbs saves the day. The idea that the only person Phineas loves and trusts is the guy who killed his Mother, is not just sad but cynical.