After Ward Haskins shoots down an old saddle tramp, Joe Flecker, Lucas McCain takes Joe to Doc Burrage but he can't be saved. Soon after, Haskins visits Lucas saying he must have something Joe had on him. Lucas doesn't know what he's talking about and throws him off the property. In town the next day, Lucas tries to find out what Haskins was looking for but the Doc tells him two children died the previous day of anthrax and the town is on the verge of an epidemic. When Mark contracts anthrax from Flecker's pony, his life is put in danger.
—garykmcd