In this gripping addition to The Rewind Society series, Rebecca Chen wants nothing more than to save her sister from a tragic drowning that happened twenty years ago. The Society offers her this impossible chance—but at what cost?

Meanwhile, investigative journalist Elena Cruz discovers that clients of the mysterious time-travel organization are vanishing without a trace. When her friend Maya disappears mid-conversation, Elena realizes these aren't just missing persons cases—they're something far more sinister.

This captivating tale weaves together parallel narratives of sacrifice, identity, and the consequences of altering the past. Perfect for fans of science fiction short stories collections who appreciate emotional depth alongside mind-bending concepts. Though part of a series, this standalone entry reads like the best classic sci-fi short stories—complete, compelling, and thought-provoking.

"The Unwritten Letter" delivers a perfect balance of heart and high concept that can be devoured in a single sitting. Ideal for those who love five minute sci-fi reads that stay with you long after the final page. Part of a broader short story collection exploring the fascinating and dangerous world of temporal manipulation.

For readers who enjoy five minute stories that pack an emotional punch alongside fascinating scientific concepts, this tale of sisters across time offers both intellectual stimulation and genuine emotional resonance.