Leaving for vacation, Mickey and Pluto arrive at a train station in Burbank, California. They board a west-bound train for Pomona, but are both immediately kicked off by Conductor Pete because dogs are not allowed. Pete then rambles off the train's destinations and forces his watch to tell him when the train is ready to leave. When the watch does show it is time for the train to go, Pete calls "All aboard!"
Mickey, at this point, decides to smuggle Pluto on board by squeezing the dog inside his suitcase. At first, the handle breaks, making Mickey almost leave Pluto behind, but Mickey recovers the suitcase and manages to make it aboard just as the train is clearing the platform. Later, Pluto barks, wanting to be let out. Mickey scolds him for nearly arousing Pete, but manages to take Pluto out and unsquash Pluto. The freedom is only short-lived, however, as Pete is coming through the train to collect tickets, forcing Mickey to squash Pluto back into position in the suitcase. After biting "Okay" in Mickey's tickets, Pete sees Mickey's suitcase containing Pluto in the seat and forcefully throws it into an overhead baggage net. This causes Pluto to bark, making Pete suspicious.
He then recognizes Mickey, who is trying to hide behind a large newspaper and make it look like the barking was coming from him. Understanding that Pluto has been stowed in the suitcase, Pete menacingly asks Mickey if he is alone. He then makes up a story about owning a little cat who'd cry when he was all alone and screams a loud "Meow!", with his face looking like a real cat, at the suitcase causing the dog to leap out. Realizing his cover's been blown, Pluto ducks back into the suitcase, but Pete has already figured it out. Before he can catch the pair, Mickey and Pluto run away and a chase ensues on board the train.
Mickey and Pluto first hide in a sleeping car where Pete mistakenly intrudes on a female passenger and gets assaulted. Pete then stumbles into another bed where Mickey and Pluto, disguised as babies, are hiding. Pete apologizes for the intrusion, but quickly catches on after realizing he was covering up Pluto's tail. Just as Mickey and Pluto are gloating that they'd fooled Pete, Pete bursts in and threatens to beat them to a pulp, but the sudden darkness, from the train running through a tunnel, allows the pair to escape, leaving Pete to beat the mattress to a pulp, and a brief entanglement with the springs.
Mickey and Pluto masquerade as a conductor by hiding in Pete's own coat and hat which they'd had taken off in the tunnel. After getting false directions from Mickey, Pete catches on and threatens to catch them, but only ends up disturbing the female passenger again. Pete receives another beating and, unintentionally taking the passenger's hat, gets pricked by one of her needles. Finally Mickey disguises himself as an Indian chief with Pluto as his papoose, but Pete eventually sees through their disguises right after Pluto bites his hand.
While Mickey and Pluto are next to an open window, Pluto is caught on a passing mail hook which whisks him outside the train. Mickey runs after him through the train, and is just barely able to grab Pluto as he exits the last car. Pete throws their luggage out after them and they fall to the ground from the mail hook. Mickey looks up at the station sign and is pleasantly surprised that they have already arrived at their destination - Pomona.
- The Mickey Mouse Club, January 21, 1958
- Good Morning, Mickey, episode #51
- Vacationing with Mickey and Friends
- Donald's Quack Attack, episode #16
- The Ink and Paint Club, episode #43: "On Vacation"
- Have a Laugh!, episode #8
- Walt Disney Cartoon Classics: Limited Gold Editions: Mickey
- The Spirit of Mickey
- Mickey and Company
- Walt Disney Treasures: Mickey Mouse in Living Color, Volume 2
- Walt Disney's Funny Factory: With Mickey
- Walt Disney Animation Collection: Classic Short Films, Vol. 1: Mickey and the Beanstalk
- Have a Laugh!: Volume 2
- There is a video of both Walt Disney and Billy Bletcher in a recording session for this short.
- Some of Mickey's and Pete's lines from this short are also heard in Get a Horse!
- The original opening and closing titles to this cartoon are presented on the Walt Disney Cartoon Classics: Limited Gold Editions: Mickey.
Have a Laugh! changes
The following scenes were deleted from the short release due to time constraints:
- Mickey walking out onto the train platform.
- Pluto sniffing a Redwood Forest poster.
- Pete rambling off the train stops and then looking at his watch to check the time.
- Mickey's suitcase handle breaking after stuffing Pluto inside and then almost leaving Pluto behind before going back to retrieve him.
- Mickey giving Pete his ticket and him punching it with his teeth.
- Pete ferreting out Pluto by asking Mickey if he is alone and then making up a story about a cat he once had (it just shows Pete letting out a meow).
- Pete beating what he thinks are Mickey and Pluto, but it's just a mattress.
- Mickey and Pluto disguising themselves as a conductor.
- Pete trying to catch Mickey and Pluto, only to run afoul of the female passenger a second time.
- Mickey and Pluto's Indian disguise.
- Mickey calling out, "Hold on, Pluto, I'll save ya!" as he chases after his dog, who is hanging from a mail hook.