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 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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