A mouse named Bigelow, whom Snagglepuss once freed from a mousetrap, is intent on freeing Snag from a zookeeper, despite the fact that the lion doesn't want to be freed. The main action takes place on a train, hence the title.

After Yogi poses as a health inspector in order to take tourists' picnic baskets, Ranger Smith sets out some booby-trapped baskets to teach Yogi a lesson.

The army has its war games in a sealed-off part of the park; when Yogi wanders in, he thinks Jellystone has been invaded.

After a flea is "evicted" from a dog's hide, kind-hearted Yakky offers to let the flea live on Chopper.

To avoid being ejected from the Adventurers Club, Major Minor tries to hunt Snagglepuss again, despite the fact that the lion is now in a zoo.

In a Medieval kingdom, Snagglepuss tries to rescue the Queen, who's been kidnapped by Count Down.

Fibber Fox disguises himself as Yakky's mother as part of a plot to get at the chickens in the henhouse Chopper is guarding.

The bears' fairy godmother grants Yogi the power to turn anything he touches into a picnic basket (à la Midas).

Snagglepuss is being transported to the zoo on a riverboat; he escapes from his cage and poses as a riverboat gambler.

Yogi and Boo Boo are tricked by the Three Little Pigs into moving into the straw house, then the wood house, just before each is blown down by the wolf. This cartoon was originally shown on The Huckleberry Hound Show.

Unable to keep up with the other migrating ducks, Yakky falls into Chopper's water dish and meets the bulldog for the first time.

Two hill people are competing for a woman's hand in marriage, and she says that she'll choose the one who brings her a lion fur coat; naturally, the suitors both hunt Snagglepuss.

Finding Yakky Doodle hiding in his mailbox, Snagglepuss contemplates eating him, but instead finds himself protecting Yakky from duck hunters.

A lady buys Yakky from a pet store as an Easter gift for her granddaughter; the lady's cat, however, has different plans for the duckling.

Sick and tired of being part of a lion taming act, Snagglepuss runs away from the circus and goes back to the jungle, expecting to be the king of the beasts.

Alfy Gator, in his first appearance, tries to catch Yakky so the 'gator can dine on roast duck.

Ranger Smith goes on vacation in Miami Beach; Yogi and Boo Boo, mistakenly thinking that they're invited, show up at the Ranger's hotel.

Boo Boo enters a mail-in puzzle contest and wins a trip for two to Paris; he takes along Yogi, who almost causes an international incident.

Snagglepuss shows up at the home of Mr. & Mrs. J. Evil Scientist, begging for food; J. Evil hires him to get rid of a mouse, which Junior had transformed into a giant.

Cindy Bear is in a circus, so Yogi runs off to join it; the circus owner get him a job as a lion tamer.

Ranger Smith tries to trap Yogi with an alarm-rigged picnic basket, and fails; later Yogi mistakenly thinks the Ranger wants him shot.

At the county fair, Snagglepuss is tired of being the target in an "African Dodger" type of game; he's talked into boxing with a kangaroo instead.

Chopper gives Yakky a trading stamp so his book will be completely filled, but the wind keeps blowing the stamp away from them.

Ranger Smith has a system of closed-circuit cameras set up throughout Jellystone so he can keep an eye on Yogi.

Using a child's chemistry set, Fibber Fox creates a formula that shrinks Chopper down to Yakky's size, and the fox chases after the two of them.