It sure looks like J.T. is trying to talks some sense into Vincent. Odds are pretty good the subject is Catherine!
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Tough luck, J.T. Tess places the character under arrest in this scene.
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Tess and JT are featured in this Beauty and the Beast scene. It's from the episode "Don't Die on Me."
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Beauty and the Beast Quotes

I won't let him hurt you.

Gabe

Tess: I'll help TJ.
J.T.: It's J.T.