Paris, July 1942: Sarah, a ten year-old girl, is brutally arrested with her family by the French police in the Vel d'Hiv' roundup, but not before she locks her younger brother in a cupboard in the family's apartment, thinking that she will be back within a few hours. Paris, May 2002: On Vel d'Hiv's 60th anniversary, journalist Julia Jarmond is asked to write an article about this black day in France's past. Through her contemporary investigation, she stumbles onto a trail of long-hidden family secrets that connect her to Sarah. Julia finds herself compelled to retrace the girl's ordeal, from that terrible term in the Vel d'Hiv', to the camps, and beyond.