Freefall by Laura Anne Gilman.

Freefall by Laura Anne Gilman. Pages 345. Science Fiction. Wren is the one no one sees. She likes it that way too. It makes her job as a retriever so much easier. Unfortunately she's tricked. She takes a job that is a trap and well I'm not telling you that part. It does lead to her deciding that the cosa need to take action against the silence. She will take them down. Even if it kills her.