Murdoch Mysteries Wiki

Jumping Jack is the fictional hero in the picture novels of the same name created by George Crabtree, "A literary innovation, it's a novel that you can read in half an hour". The picture book illustrator is Gregory Heckenbush, an engineer by training who insisted that all of the devices be feasible.


Crabtree is considering renaming his hero because he does more than jump. In the second installment, he has all manner of devices:

  • spring loaded in his boots
  • a rotorized aero pack that allows him to fly
  • wheels on his shoes, which allow him to move quick as a flash
  • the extend-o-arm
  • the magnifying spectacles
  • the sleeping gas ball

Crabtree based Jumping Jack on Detective William Murdoch who always seeks justice and invents things, combining those two qualities into one extraordinary man, "... supreme hero, if you will."  But Murdoch doesn't know this and George is happy to keep it that way, when Jumping Jack inspires a real life thief.

Appearances and Mentions

Once Upon a Murdoch Christmas

A series of puzzling thefts that suggests somebody is using the devices from his picture novel leads George to believe his fictional hero may have come to life. The constable feels responsible for the Christmas crime wave. Toronto Station Houses all report thefts of gift-wrapped parcels from Eaton's Luxury Department as their distinctive wrapping makes them easy to target. The Toronto Gazette headlines read, "All hail Toronto's Robin Hood”– robbing from the rich and giving to the poor. While thief’s heart may be in the right place, the constabulary has to stop him.

When George and the Detective chase the thief masquerading as Jumping Jack, they witness his escape using the rotorized aero pack: "Oh my God, it actually works!" Murdoch turns to Crabtree, "This is no cause for celebration, George."

This reprobate has stolen Christmas right from under everyone’s noses: "If it wasn't for my rampant imagination and fantastical literary prowess, Jumping Jack wouldn't exist, and this criminal wouldn't be inspired to reach even greater heights of enterprise...I created this monster. I might as well be committing these robberies with my own two hands." The Inspector offers to prepare a cell for him, adding, "Crabtree, no one even bought your little picture book."

Actually six copies of the first issue were sold. Admittedly none of the second, but…the rotorized aero pack only appears in the second issue, there's only one person who has that issue. Upon questioning Crabtree's first and only fan Miss Vicky Parsons, the Inspector finds it hard to believe that the sixteen-year-old girl could build the aero pack. Besides, she only got the picture novel yesterday. But, another robbery is committed during that interview.

Miss Parsons isn't the only person privy to the idea of the rotorized aero pack. Murdoch and Brackenreid interview Mr. Heckenbush who was able “to force a smidgen of reality into what was otherwise nothing but fanciful nonsense”. So theoretically every invention in the picture book can work, “Of course Mr. Crabtree refused to acknowledge the limits of the capacitors that powers the devices. He had Jack flying all over town, when in reality he'd barely make it two city blocks before plummeting to his death.” While the technology exists to build the components of each device, it is far too costly for him to bring his illustrated schematics to reality. Any number of people have seen the drawings– illustrations: the printer, the typesetter, the delivery boy, the postman, the grocer, the...

Later, Mr. Heckenbush reports the discovery of the Mechanized Leg Extender in one of the trash bins near his place. It works on the same principle as the Extend-o-Arm, compressed air forces the nested sections outwards. He drew the specifications at Mr. Crabtree's insistence, but realized it would never support a man's weight. Someone built it and chucked it away when it failed. “Then perhaps our Mr. Jack lives somewhere nearby.”

Murdoch with the Inspector and Crabtree find the thief’s lair: he did steal the schematics, solving the mystery of how he was able to build to devices. George is stunned, “ I don't know what to say. I'm amazed and disturbed in equal measure. To see my vivid imagination made flesh, as it were...” The place is rented to a Mr. Robert Fields– the man in Customer Service at Eaton's department store, but Crabtree discovers Robert Fields is gone.

Back at the Station House where all of the devices and schematics are being examined by Murdoch, George points out “All this…this must really be like Christmas for you isn't it?” “Yes, I suppose it is.

The next morning, they discover Murdoch’s office has been broken into, but only the Sleeping Gas Ball is missing… to be used for the next robbery! The target: The Ice King's Winter Banquet at The Aberdeen Club!