Room 4B

Eighteen families in one chat. One of them knows it wasn't an accident.

On a sunny Saturday in May, nine-year-old Toby Nash falls from the old climbing frame at Larkmoor Elementary - during the exact eleven minutes when a dozen parents were staring at the same glowing screen. A tragic accident, everyone says.

Until an anonymous account appears in the class group chat and claims otherwise.

Greer Whitlock used to unmask people for a living: by their typing patterns, their phrasing, by what the data gives away. Now that gift turns on her own family - because the account quotes something only her husband could know. And then it writes to her directly:

I know what you did, Greer.

Between the school gate and Parents' Night, between friendship and suspicion, Greer digs toward the truth. A loosened bracket. A line of handwriting. And the realization that whoever looked away didn't look away at all - they watched.

A psychological thriller about how fast a group becomes a single suspicion - and who was really looking when it counted.

For readers who like their suspense cold and precise: no gore, no serial killer - just a neighborhood where everyone has something to hide.