March 1941.
The Italian Navy's Enigma codes were unbreakable - until teenager Mavis Batey noticed something impossible.
One missing letter.
Three sleepless nights.
The result: the most devastating naval ambush in modern warfare.
While Italian Admiral Iachino commanded the Mediterranean's most powerful fleet, a 19-year-old university dropout at Bletchley Park was reading his every move.
This is the story of how intuition defeated mathematics, how a procedural error doomed an entire fleet, and how the Battle of Cape Matapan became a 2,303 to 3 massacre because someone noticed what shouldn't be there.
The Italians never discovered that someone had broken their codes.
They never learned that a teenage girl destroyed their naval supremacy in 68 hours.
She went on to raise a family and study gardens, never speaking of her wartime work until historians found her decades later.
Sometimes genius comes from the most unexpected places.
