Get ready for a CBS crossover event -- well, sort of.

According to TV Guide, Dylan Bruno will guest on the last two episodes of 'NCIS' this season. Bruno, who played Colby Granger on 'Numb3rs,' will be playing a military man connected with the Gibbs' nemesis Colonel Merton Bell (Robert Patrick).

For more details and SPOILERS, such as they are, follow the jump.
The Bell character heads up a professional army -- a pseudo Blackwater -- armed with veterans who are happy to be part of his mercenary corps. Dylan Bruno is going to be one of Bell's minions, Lt. Jason Paul Dean. Dean's an ex-Army Ranger who had received medals for his feats of courage and heroism. Then something went wrong in Afghanistan and he was dishonorably discharged. Presumably that's left a bad taste in his mouth and his bitter. He's also ready, willing and extremely able to take part in Colonel Bell's private war games. He's a stone-cold killer when put to the test.

As mentioned, Gibbs has dueled with Bell a few times this season. And Allison Hart, Rena Sofer's character, has a definite link to Bell; she was the attorney representing one of Bell's soldiers in a previous episode. Since then, Hart has remained in contact with Gibbs and there's something brewing between them.

However, in typical 'NCIS' fashion, if Jethro and Allison are more than friends -- and they flirt like they might be -- the producers have yet to show it to us. The fly in the ointment for their romance, of course, is whether Gibbs can trust her or not. Gibbs is the kind of man who's been burned enough times that he doesn't trust easily, and he's still never really gotten over losing his first wife, Shannon, and their daughter, Kelly.

What can we expect from Lt. Dean? Hard to say, based on the limited information. But according to what producers recently told Entertainment Weekly, Gibbs "has to make a devastating choice to save his team." Does Dean take aim at Tony or McGee or Ziva, forcing Gibbs to sacrifice himself to protect his people? That would seem highly probable.

Mark this in your calendar: the 'NCIS' season finale airs Tue., May 25 at 8PM.