Luke is at a police station in this Modern Family scene. It is from Season 5.
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Mitch and Cam start searching for wedding venues on Modern Family. "And One to Grow On" is the 11th episode of the show's fifth season.
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Modern Family Season 5 Episode 11 Quotes

Driving with Alex is torture. She drives so slowly, I have to be the only parent who slams on the imaginary gas.

Claire

He keeps resisting but it's in his blood. I come from a long line of dancing Dunphys. A kickline actually.

Phil