JLo is Jenny From the 'Value Shop'

JLo is returning to her roots ... even though it's just for a new movie.

Lopez was spotted Monday at a market in Queens shooting scenes for "Second Act."

The superstar wore a Value Shop uniform ... and even pretended to take public transportation.

Now, that's acting.

!youtube-embed(https://www.youtube.com/watch?v=dly6p4Fu5TE)