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Alias: Dr. Samuel Register
Teen Titans Adversary

Related Links: Beast Boy (Garfield Logan) TT


Shifty Character

Doctor Samuel Register shared the lab with Mark and Marie Logan when their son Garfield was infected with Sakutia, a rare tropical disease that was believed only animals could survive. In a desperate move to save his son, Professor Logan treated Gar with an untested machine which he originally developed to isolate the common genetic bond shared between humans and animals. Gar recovered, but a side effect turned his skin green. A few years later, Gar learned he could transform into any animal he could imagine.

Register became obsessed with recreating the experiment that gave Gar Logan his powers – to discover the missing link between man and animal. His career became littered in scandal because of his unorthodox methods. He earned the nickname “The Zookeeper” when he was at the government’s animal research center in Tampa. When he was discharged for his extreme methods, S.T.A.R. Labs’ San Francisco branch hired him to lead their abnormal and extraterrestrial disease program.

Zookeeper explains his plan in TEEN TITANS #15 [2004].

Beast Boys and Girls

When the children of San Francisco were infected with the Sakutia virus, it created a community of animal-transforming boys and girls. Beast Boy was believed to be the virus carrier, until Dr. Sam Register was brought in the case as an advisor. Register revealed that Beast Boy wasn’t the carrier – he was. Borrowing a sample of the Sakutia virus, Register altered it and unwittingly infected himself. His skin now a scaly purple, Register discovered he had shape-shifting powers similar to that of Beast Boy.

Seeking a cure, the doctor tried to cut Beast Boy open to learn his biological secrets. But the Teen Titans saved their teammate and Beast Boy himself brought down The Zookeeper in a shape-shifting battle through San Francisco. Using Dr. Register’s blood, the children were all inoculated and cured. The Zookeeper was brought to Alcatraz prison. Somehow immune to any cure, the shape-shifting mad doctor plotted his revenge.

Primed For Vengeance

The Zookeeper was later presented with an opportunity for revenge, when Superboy-Prime gathered his own “Legion of Doom” comprised of various Titans villains. But Teen Titans past and present were able to contain the criminals and trap Superboy-Prime within the impenetrable Source Wall at the edge of the universe.

Zookeeper joins Superboy-Prime’s Legion of Doom in TEEN TITANS (third series) #100 [2011].

 Powers & Abilities

Just like Beast Boy, Zookeeper can transform into any animal.


 Essential Reading

Teen Titans #13-15 [2004]: “Beast Boys and Girls,” Part 1-3: An entire school has been infected by the rare virus Sakutia – the disease that transformed Gar Logan into Beast Boy. Now the Titans are out to cure the kids, and the parents are out to hang Beast Boy – for being contagious! But the real culprit is Dr. Samuel Register, who has transformed himself into the shape-shifting Zookeeper. First appearance of Samuel Register in issue #13. First appearance as Zookeeper in issue #14.
Teen Titans (third series) #99-100 [2011]: It’s all-out war as Titans old and new come together to face the greatest threat to their existence. Superboy-Prime gathers his own “Legion of Doom,” comprised of various Titans villains. He then creates an army of Superboy clones to besiege the Titans. Together, Titans past and present defeat the villains and trap Superboy-Prime within the impenetrable Source Wall at the edge of the universe.



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