In 1954, Melbourne is still reeling from WWII; the Cold War sees suspicions running high and the threat of communism and spies hide in every shadow.
Jewish schoolgirl, Ruth, is trying to navigate her own path, despite her strict upbringing and the past that haunts her family.
It's a path that she wishes could include her first love, Patrick, but the rich Catholic boy is strictly off limits.
When a mysterious woman moves in next door in the dead of night, Ruth is convinced she is none other than Eva or Evdokia Petrov, a Soviet spy and wife of the infamous Russian defector, Vladimir Petrov.
Could Ruth's unlikely new friend really be the most sought-after woman in Australia?
Will Ruth's own clandestine meetings with Patrick be discovered?
How does the Petrov Affair, as it became known, impact the life of one ordinary girl and her family?