Blue Bloods Blue Bloods

On the Blue Bloods set, it's not uncommon to see fake handguns, mock suspect files, claustrophobic interrogation rooms ... and dance numbers?

"We have dance-party Fridays!" Jennifer Esposito tells TVGuide.com after grooving and clapping with the crew to Donnie Wahlberg's beatbox tune in between takes. "It's our little way of unwinding as we wrap up [an episode]." She pauses. "We know it's Thursday today!"

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