Henry must find a cure when an ancient virus is released.

When a gang of thieves try to steal a WWII computer, Maggie, Jasper and Henry are cornered in the museum, unable to escape.

Investigating a strange "stone," Henry and his friends discover that the object is actually the remains of the Soviet satellite Sputnik - that's wanted by Russian mobsters.

Henry's parents decide that it's best for him to go to a high school after traveling the world. In his new school, he meets new friends and uncovers a huge secret.

A traveling Samurai exhibit, rumored to be haunted, comes to the museum. When, Henry discovers that some of the exhibit items are being stolen, he is not believed by his uncle. Henry, Maggie and Jasper therefore try to take matters into their own hands, shadowing a martial artist, who they suspect is the thief.

Inside a trunk, Henry encounters artifacts, which guide him to a discovery by Ponce de Leon.

Henry stumbles upon a secret in the Dillinger car.

Henry runs into an old friend and rival from the past. Henry believes that this friend's father may be targeted for assassination.

When a ruby, which is supposed to be cursed, ends up stolen, Henry and his friends try to find the ruby and return it to the museum.

After a teenage magician makes a Senator's son vanish, using an old magic trick of Houdini, the disappearance is investigated by Henry.

Henry tries to clear his uncle's name by solving the murder of the former partner of Jasper's father and finding a Viking artifact that he was looking for.

The gang discovers an extinct beetle species.

Henry follows a clue trail left by George Washington as a school election pits Jasper vs. Maggie.