The Hitchhiking Ghosts are the main villains a trio of famous ghosts that are located near the end of The Haunted Mansion in the Disney theme parks. They rarely appear as face characters, only appearing during events such as the ride's 40th Anniversary.
They sometimes appeared on the animated television series Disney's House of Mouse. They also had a minor role in the 2003 film The Haunted Mansion. The Skeleton, however, did not have a speaking part. Their official names are Phineas (Traveler), Ezra (Skeleton) and Gus (Prisoner).
In Sorcerers of the Magic Kingdom, they have their own spell card called "The Haunted Mansion's Happy Haunting Grounds". It was only available to guests that attended Mickey's Not-So-Scary Halloween Party in the fall of 2013.
The Haunted Mansion
The Hitchhiking Ghosts appear towards the end of the Haunted Mansion inside of the Mausoleum where the Ghost Host tells the guests, "Ahhh, there you are. There's a little matter which I forgot to mention, Beware of Hitchhiking Ghosts. It appears that they've selected you to help fill our quota, and they'll haunt you until you return". The Ghosts then appear sitting beside the guests in the their reflections and proceed to haunt the guests in an effort to have them return to the Mansion, dead or alive.
Through this brief appearance in the attraction, you can assume that the three along with being residents of the Mansion, are also a form of employee for the estate and that they have the job of finding new guests to help fill the Haunted Mansion's quota.
The Ghost Gallery
The Ghost Gallery was an unofficial series of Haunted Mansion character biographies created by Disney World cast members in an effort to add more mythos to the attraction. This story proved so popular that it was responsible for creating the hitchhikers official names, those being Phineas, Ezra and Gus.
Professor Phineas Queeg was a discredited chemist turned snake-oil peddler who was committed to the New Salem Insane Asylum after having sold a "miracle elixir" which caused the man who drank it's voice to raise an octave. Phineas wound up escaping with Ezra and Gus and they hitchhiked away together. The professor died from lead poisoning after he cut his lip on one of his elixir bottles.
The Ghost Gallery's backstory for Ezra the skeletal hitchhiker is extremely inappropriate and features mature implications, gives his character perverted characteristics, and the story features misogynistic weight-shaming. In the backstory Ezra Dobbins was disgusting criminal who enjoyed stalking overweight women, breaking into their homes, and watching them as they changed. After having been arrested for breaking into the boudoir of the mayor's ample daughter was sent to the New Salem Insane Asylum because the judge and jury believed he must be insane due to his interest in overweight women. Ezra wound up dying while peeping on the "Fat Lady" of a circus when she accidentally sat on him.
Gus Gracey was a genetic dwarf from Ohio who as a child killed his family pets and attempted to murder his siblings on several occasions. His parents ultimately had him institutionalized in the New Salem Insane Asylum but he eventually grew up and wound up hunting down his parents and subsequently murdered them. Gus then shipped himself inside of a crate to his cousin George Gracey's mansion in an effort to kill him, only to be imprisoned in one of the mansion's secret rooms. When the mansion was inherited by George's son Master Gracey, Gracey had his clairvoyant Madame Leota place a curse on Gus to imprison him on the mansion's grounds. Gus wound up dying while trying to throw his ball and chain at a cat sitting by a well, resulting in Gus's iron ball falling down the well, killing him.
The Haunted Mansion (comic book)
They appear in the main story was well as all of the bonus and side stories. They never say anything but attempt to hitchhike, they succeed at one point but scare the cab driver killing him and wind up back at the mansion with the cab driver joining them as a new resident.
Each ghost got a side-story telling of their lives before they came to the Mansion.
Gus was a Shepard who only wanted to get some sleep but everywhere he went had bad luck until he was arrested in Port Royal until he died and found his way to the mansion. He soon wants to leave since the other ghosts parties keep him awake and joins Ezra and Phineas.
Ezra Gasser was a prankster since childhood that ran a successful practical joke business when he got older. Seeking out new jokes to help his business, he discovered Chinese finger traps from a mysterious salesman, but found himself unable to free himself. He laughed himself to death and was then invited to the Mansion. However, his pranks made the other ghosts angry, resulting in him joining Phineas and Gus.
Phineas Q. Hackenbush was a snake-oil salesman that was chased by an angry mob given snake tongues by his "miracle cure" product off a cliff. After being invited to the Mansion, he kept his business going, but when Madame Leota reminded everyone that they were already dead, and he was chased out, joining Gus and Ezra.
House of Mouse
They appear in several episodes, most noticeably in the episode "House Ghosts", where they are freed from a crate and sing "Grim Grinning Ghosts" along with other residents of The Haunted Mansion such as the Bride, The Executioner and the Hatbox Ghost as well as the Lonesome Ghosts and the Skeletons from The Skeleton Dance. Where they scare Pete out of the club.
In the made-for-DVD movie, they are freed from a crate by Cruella De Vil and join the villains in the song It's Our House Now! as they take over the House of Mouse. Aside from scaring the guests, they don't appear to be doing anything bad and are just happy to scare the guests. Later they are seen watching the final battle between Mickey Mouse and Jafar. After Jafar is defeated, they flee with the other villains.
The Tokyo Disneyland version of Star Tours: The Adventures Continue features three Audio-Animatronic droids (one being a former RX-24 from the original Star Tours) positioned near the end of the queue in a manner similar to the Hitchhiking Ghosts.