Broken Hearts is a novella written by R. L. Stine. It was the fourth book in the Fear Street Super Chillers book series and was first published in 1993.
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There’s someone out there, someone who kills on Valentine’s Day. Josie and Melissa are scared—especially when they receive threatening valentines. Then the murders begin. Who is sending these horrible valentines to the girls of Shadyside High? And who will be the next to die?