Jon Huertas, Will Rothhaar Jon Huertas, Will Rothhaar

Something tells us Castle's Esposito might be swearing off public transportation soon.

On Monday's episode (10/9c, ABC), Esposito (Jon Huertas) and a group of passengers on a subway train are taken hostage by a mysterious gunman. It'll be up to Beckett (Stana Katic) & Co. to figure out the gunman's motives and help Esposito bring the hostage standoff to a peaceful conclusion.

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But that may be easier said than done. For starters, as seen in the exclusive clip below, Beckett has to deal with a highly emotional Lanie (Tamala Jones). "He has been in worse scrapes than this and we are going to get him out of there, I promise you," Beckett says. 

But just when Beckett thinks they've caught a break that gives them an advantage, they realize the gunman has another surprise hidden under his coat. 

Click play below to see exactly what Esposito is up against. Castle airs Mondays at 10/9c on ABC.