Book #2 in the Mission Inn-Possible Cozy Mystery series.
Charlotte Mission is "not interested in getting involved in another murder investigation. That is until the local librarian is slain and her ex-spy grandmother is fingered as the one whodunit. Charlie’s got to solve the mystery before grandma’s secret stash of weapons—don’t ask, don’t tell—is discovered, and they’re both carted off to federal prison. Or worse. But that’s not going to be easy, what with another agent snooping around, a literal fire to put out, and a new kitty shelter to run. She must solve the case before grandma goes to jail. Or breaks out of it."