This is book 4 of the "Phryne Fisher" series.

This note contains spoilers for the book.

Her windshield gets shot out while driving by the docks, and she finds a body in the road. And ruins her dress.

She's enraged at lots of this, including the loss of human life, and plans to get revenge. Anarchists are involved, and communists, revolutionaries of all stripes.

When Dot gets kidnapped, though, she's ready to pull out all the stops. Dot does fairly well herself, but the rescue effort intersects her own work quite usefully, and she is in fact rescued.