Survived (Revived, #2)

Waking up locked inside a container is something Vivian was not expecting. She knows she died before she could complete her previous mission, but why was she put inside the container?
However, once she frees herself, she learns that people are not only living underground, but in an isolated town outside, where the air was pronounced to be toxic. But this town has been around for years, so who are these people? Once Vivian gets involved with them, she can't pull herself out. Someone from her past is right around the corner.