Heart of barkness

"They're both music lovers, so when Lotty Pilgrim, a country singer from long ago, turns up at a local bar, they drive out to catch her act. Bernie's surprised to see someone who was once so big performing in such a dive, and drops a C-note the Little Detective Agency can't afford to part with into the tip jar. The C-note is stolen right from under their noses--even from under Chet's, the nose that misses nothing--and before the night is over, it's stolen again. Soon they're working the most puzzling case of their career, a case that takes them back in time in search of old border-town secrets, and into present-day danger where powerful people want those secrets to stay hidden. Chet and Bernie find themselves sucked into a real-life murder ballad where there is no one to trust but each other."--Publisher's description.