History
Professor Chalis was a scientist during the days of the American Frontier. He studied his practice in Chicago and was obsessed with turning men into giants. He studied Duval's theory on controlled cell growth using prismic light rays as the groundwork for creating a growth ray device. He tested the device out on a human subject named Zugg. The device worked, however as a side effect those exposed to the ray also lost their intelligence. Soon the scientific community learned of Chalis' experiments and denounced them. When meeting with his colleagues, Chalis refused to stop his work prompting his colleagues to contact the authorities.
Chalis decided it was time to leave town, choosing to move to the American west where he could continue his experiments with little interference. When he arrived at his lab he found that Zugg had murdered two police officers who had been dispatched to confiscate his scientific equipment. Gathering what they could, the pair then fled the state and eventually settled in a manor outside of Leadville, Texas. There he continued his experiments for six months, and began romancing Marie Lathrop daughter of local rancher Jim Lathrop, much to the chagrin of local doctor Matthew Masters who was secretly the western hero known as the Black Rider. Chalis first began experimenting on animals, such as wolves and rattle snakes but eventually moved onto bulls, sending Zugg out to steal them from the Lathrop ranch. When the news of the missing bulls got out, Masters investigated as the Black Rider, following Zugg's foot prints to the Chalis mansion where he was attacked by an enlarged wolf, which he killed and then fled the scene.
The following day, Professor Chalis invited Marie into his home to show off his work. When showing her his growth ray, Marie was frightened by the appearance of Zugg, causing her to accidentally turn on the device when she bumped into the activation lever. The ray struck Professor Chalis out, prompting Marie to get Doc Masters to look after him. Giving Chalis a clean bill of health, Masters and Marie left. However, Chalis was driven insane by the rays effects and he decided to experience the growth effect himself, but developed an antidote so he could reverse the effects later. He then began capturing ranch hands from the Lathrop ranch and experimenting on them as well. However one named Jim managed to escape. Now completely mad, Chalis also kidnapped Marie in front of her brother Bobby who rushed to tell Masters what happened.
Master meanwhile had an encounter with Jim and realized what Chalis was up to. As the Black Rider, Masters stormed the Chalis mansion but was forced to face defeat at the hands of Zugg when Chalis put Marie in danger. The pair found themselves tied up and in the path of the growth ray. However, before Chalis could activate the device, Jim and the other giants revolted destroying the ray device in an explosion that killed Professor Chalis. In the aftermath, Black Rider's horse Satan freed his master and Marie, as well as slew Zugg. As the Chalis mansion burned down, the Black Rider administered the antidote to his surviving victims restoring them to normal, ending Chalis' insane experiments.