This episode starts with Portia and Bingo playing a game of marbles. Portia knocks one out, making it another one for her (and she has a gigantic pile next to her) and none for Bingo. Bingo then bets Portia all his marbles that he'll hit three marbles with one shot. "You're on!" Portia shouts. Bingo shoots his marble, but misses, and the marble ends up inside the caboose, and in Zipper's mouth, waking him up from his "cat nap." He comes out wanting to know what's going on. Portia tells him that "Bingo made a bet and lost all his marbles!" Zipper then goes on to tell Bingo that betting is for suckers. Just then, Dotty, Woolma, and Montgomery come running by, telling the others that there's going to be a rowboat race, and Montgomery signed up. Bingo knows Montgomery will win for sure, and tells him that he's going to arrange a big surprise for when he wins. Dotty points out that Montgomery won't win if he doesn't train, and Bingo offers to help, but catapults himself over to a tree branch, and ends up hanging there by his tail. Zipper suggests he help by NOT helping.
Elsewhere, Leland is building a clubhouse for Catchum, and is about to pound the last nail in, when Catchum calls, causing Leland to pound his thumb with the hammer instead of the nail (WHAM!) Catchum yells at him to "stop clowning around and get down here," which Leland does, but only after the clubhouse he's building falls apart, and he ends up landing in the water (send the kid to carpentry school!) Catchum tells his sidekick that he's entered the rowboat race, and is going to beat every kid in town, including Montgomery. Leland points out Montgomery's strength as an asset, but Catchum plucks him out of the water, holds up a saw, and tells him that "being prepared is what counts."
When the race starts, Montgomery wishes Catchum good luck, but the gesture is returned by Catchum telling Montgomery to save his breath (he'll need it). Montgomery pulls into an early lead, until his oar is sawed in half, and he's out of the race. Catchum pulls ahead and wins, much to Bingo's dismay, and he slinks off.
Back at the clubhouse, the gang is wondering how Montgomery's oar broke, when Catchum and Leland come in. Catchum pulls a piece of paper out of his jacket and tells Montgomery to "read it and weep." It turns out to be a bet signed by Bingo, saying if Montgomery won the race, Catchum would have to pay Bingo ten gallons of chocolate wood chip ice cream, but if he lost, Catchum would get the clubhouse. This causes an uproar among the gang, but since there wasn't any cheating involved, it was a fair bet. Zipper's suspicions are aroused, so he goes to find Bingo while the rest of the gang leaves the clubhouse.
Bingo is sitting by the river when Zipper comes up to him. The two of them realize Catchum pulled a fast one, and Zipper goes to get the rest of the gang to "stage an eviction," but Bingo goes to the clubhouse to set things straight himself. He confronts Catchum and makes a grab for the paper. Catchum picks up a cake and throws it at Bingo, who ducks, and it hits Leland instead. Leland stumbles backwards and hits the brakes of the caboose (and goes for a "spin" on them in the process), causing the caboose to start rolling down the train tracks.
The rest of the gang is sitting in Hoofnagel's Ice Cream Emporium as their temporary clubhouse. Mr. Hoofnagel is about to object when Zipper burst through the door. When he opens the door, he hits Mr. Hoofnagel (WHACK!) and sends him flying across the room. Zipper reports that Catchum tricked them and are about to head to the clubhouse when Portia notices that it's coming to them! The gang watches as the caboose rolls by, and chase after it.
Meanwhile, Leland is trying to put on the brakes, but the mechanism is stuck. Catchum pushes his sidekick out of the way, and tries to turn it himself, but he pulls the wheel off instead, and the caboose is still rolling down the tracks. The tracks finally run out, and the caboose rolls onto a raft, and starts floating down the river. Montgomery picks up a nearby stick and pole vaults to the caboose (despite a protest from Dotty). When Montgomery arrives, Catchum tells him the gang can have the caboose back if Montgomery gets them out of this mess. Montgomery agrees and pulls a rope out of a toy box, telling Catchum that they'll have to work together. Catchum declines, pushes Montgomery out of his way, and rummages through the toy box, pulling out a pogo stick. He's about ready to bounce out of the caboose when Leland jumps on his back, blocking Catchum's line of vision. The two bounce out of the caboose and crash into a nearby tree (WHAM!)
Zipper, Dotty, Woolma, and Portia are still chasing after the caboose, and notice it's heading right for a waterfall. Montgomery throws the rope to the others and ties one end to the caboose. Zipper ties the other end to the tree just in time. Montgomery and Bingo climb out and regroup with the rest of the gang. Woolma is upset that the gang's clubhouse is stuck in the water. Montgomery claims that the gang will just push it back to the tracks, since they're not far from the river. Woolma doesn't think it will work, but Bingo is so sure it will, he's about to bet the caboose again, but Zipper covers his mouth with his hand to stop him. Zipper then makes a bet of his own, asking the others how much they "wanna bet" that he can keep Bingo's mouth shut for the rest of the day, and the gang starts laughing.