play on heartstrings
play on the/(one's) heartstrings
To elicit a very strong emotional reaction in one, especially a feeling of sympathy, pity, or compassion. I don't know why, but that piece of music always plays on my heartstrings. That documentary really plays on the heartstrings—you'll want to adopt all of those kids after watching it. Can't anyone else see that all her tears and wailing are just an act to play on people's heartstrings.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
play on someone's heartstrings
Fig. to attempt to get sympathy from someone. She is crying so she can play on your heartstrings and try to get you to take her home.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.