Firefly: The Ghost Machine - book 3 of the series
Mal and crew have taken a transport job from Badger and something about it doesn't feel quite right. They need to pick up an unknown crate from a distant planet and deliver it to Badger on a tight schedule, no questions asked. However, Mal does have questions and he plans to ask them. When they finally arrive at the pickup point a little bit late, it puts both sides on edge. When Mal asks the other group what's in the crate it just escalates the situation. The well armed individuals with the crate aren't talking and their guns are ready to back up their silence. Mal's gut tells him this is a bad deal so he decides they need to pull out. Then in a very Firefly fashion, one thing leads to another and it all goes sideways. Mal's instincts were right, but they were also too late, as the Ghost Machine is already starting to affect him and the crew and they may not survive the experience.