So finally, here we are.
The last part of this season starts with a really nice and out of the ordinary episode; in which we learn the basics of the plot that will be continued in the next episode(s).
Arms dealers, "super-cool technologic toys" and secret agencies are the main characters; Gibbs and the team must cooperate with the NCIS OSP in LA to catch the bad guys... in the meantime Tony's curiosity about Ziva's secret guy starts to make tony suspicious.
Nice episode; clearly plotted to introduce the new characters and the events for the next episode, so could be considered as a filler, well sorta.
The party has just begun...