Snapshot

Two little girls, frozen in black and white. One picture worth killing for.

The Civil Rights Movement is less than a distant memory to Lisa Waldren—it is someone else’s memory altogether, passed on to her through the pages of history. Her life as a federal prosecutor in Boston feels utterly remote from the marches in the South that changed her father’s generation—and the entire nation—forever.

But the truth is, she was there.

When a photograph surfaces showing a blond, four-year-old Lisa playi...