Someone has doctored Dr. Herkimer's Ozono, sovereign remedy for gout, cancer, spastic colon, excessive wind, heart palpitations, and all other complaints and conditions. The potion might not have anything good in it, but it never killed anyone before now. For Lobo, a paralyzed former lawman, it's a puzzle: Why would Herkimer poison the goose that's laying the golden egg? When Le Four's sheriff becomes one of the potion's victims, Quinn Booker finds the badge pinned to his own chest, and while trying to keep the townspeople from lynching Herkimer, he discovers that he has another problem. Paul Muller, the last man arrested by Lobo before he was backshot, has escaped from prison and is on his way to Le Four to get what's his. Since Lobo thinks his ex-partner, Lucius Jenkins, has found greater profit on the criminal side, possibly being part of Muller's plan, Quinn's investigations begin to threaten too many people with too many secrets.