Beneath the placid facade of Canberra, senior political journalist Harriet Dunkley uncovers a secret city of interlocked conspiracies, putting innocent lives in danger including her own.

While searching for evidence, Harriet ruffles feathers -- including those of her new boss. Meanwhile, pressure mounts on Robbie.

The video's fallout wreaks political havoc, Mina asks Harriet to make a special delivery, and Cal is brought in for questioning.

Harriet turns up the heat on Helen. Lockhart entrusts Sullivan with a low-key mission. Karen pushes to be part of an elite committee.

Vaughn breaks the rules in more ways than one. Karen worries she may be compromised. Cal demands a sit-down with the prime minister.

Harriet searches high and low for a missing piece of evidence that may prevent a war. Markson comes home. Karen receives a disturbing message.