The Galinders – two brothers and a son – move to Walnut Grove, where they immediately begin causing trouble. Rev. Alden pleads patience and to "turn the other cheek," but the Galinders do everything to test the patience of Walnut Grove's citizens.
Running up bills at Olesen's Mercantile and Hansen's Mill, and not paying despite their promises, are just the start of the problems. The son (whom Nellie falls for) is a bully at school who tries to make a pass at Mary and later, harasses Miss Beadle; both of them are struck at least once.
Meanwhile, the brothers begin to vandalize the town's businesses when they are asked to pay their bills. But the Galinder brothers press their luck once too often when they make a pass at Caroline. An enraged Charles confronts the brothers but ends up getting beaten.
Finally, word spreads about what happened. The school children stand up to their bullying classmate. Rev. Alden, having lost patience with the Galinders, invites the brothers to Sunday service, where he preaches a special sermon about Hell and the Devil's workers and orders them out of town, under escort from the men.