Improv Everywhere, a New York City-based improvisation group, "causes scenes of chaos and joy in public places" by executing undercover missions around the city. Founded in 2001 by Charlie Todd, the company enlists actors, called "agents," to go around and pull good-hearted pranks to make people smile.

As a follow-up to their 2008 Food Court Musical, Improv Everywhere, created Grocery Store Musical in recent weeks. With a song by longtime members Scott Brown and Anthony King (creators of the Off-Broadway Gutenberg! The Musical!), Grocery Store Musical takes six agents, all actors from the Upright Citizens Brigade Theatre, and places them in a "Best Yet" grocery store in Astoria, Queens. Filmed entirely with hidden cameras, not only is Grocery Store Musical caught on tape, but so are the reactions of the shoppers.

Take a look:

To see more fun Improv Everywhere missions, go to improveverywhere.com.
—Allison Klamkin