The following are a cast of minor characters in the Atomic Robo comic book series.

Charlie Simmons[]

Charlie Simmons was one of Robo's friends and fellow pilot during his time with the Flying Tigers in 1940. He was a known alcoholic, often challenging Robo to drinking contests, much to the fact that Robo doesn't have a mouth or a digestive system. He died from cancer in 2007, and her granddaughter sent Robo a letter and a picture Charlie took of him at that time, thanking the robot for being her grandfather's friend.

Hosni Mubarak[]

The president of Egypt made an appearance during a mission when Robo and his team of Action Scientists had to subdue a hostile, mechanical pyramid before it destroyed the city of Luxor. The president strictly told not to destroy it, but when that failed, he ordered his men to attack near them. When Robo proposed to forgo the fees to the mission, he was reluctant until another threat came along and drove his army away.

Carl Sagan[]

Main article: Carl Sagan

Carl Sagan makes multiple appearances in the series. He first came into contact with Robo when the robot proposed to him to build a device that could contain and study The Shadow From Beyond Time. He took a liking to Robo after that event and asked him three years later to examine the landing craft for the Viking I mission to Mars, offering to be its escort in space.

Stephen Hawking[]

Stephen Hawking makes an appearance in the issue as the man who wrote up a fake psychological evaluation of Robo for the Viking I mission, prompting Carl Sagan to take Robo as an escort for the boring, two-year round trip to Mars. In retaliation, Robo carved a message just for him on the planet's surface. It appears as if the two dislike each other.

Jack Parsons[]

Jack Parsons was an occultist rocket propulsion researcher who created a magic-powered spaceship and flew it over Southern California in 1947. Robo was able to stop him before the faulty design of the rocket caused it to crash into the city.

The Ghost of Rasputin[]

Thomas Edison, envious of Tesla's success over his atomic robot, attempted to assassinate the robot using his Necrophone to summon the ghost of Rasputin and destroy the lab in the process. Robo was able to destroy the ghost by blasting it with a prototype Lightning Gun. Much like a spiteful, evil ghost, Rasputin spoke in a howling, Russian voice demanding Tesla's head.

Sargent Hovarth and Lieutenant Everett[]

Main article: Lt. Everett

Charles Fort[]

Harry S. Truman[]

First Appearance: MXII - 1 of 4

James Forrestal[]

First Appearance: MXII - 1 of 4

Nikola Tesla[]

Main article: Nikola Tesla

Nikola Tesla, known as the father of modern electricity and the inventor of alternating current, is the creator and father figure of Robo. After settling down in his Houston Street laboratory, he spends his days tinkering with outlandish experiments, contemplating the universe in his armchair, sleeping, and subsisting on a diet of crackers divisible by three and warm milk.

Robo serves as his lab assistant before he left for China to fight during World War II, living alone until his inevitable death in January 7, 1943.

Howard Philips Lovecraft[]

Rex Cannon[]

A slightly pompous, smug prospective employee of Tesladyne, his experience as a Marine and a Navy Seal as well as multiple PhD's in advanced, unknown fields piqued Robo's interest... until he got dragged down a pit of hungry vampires and presumably killed, serving as a catalyst for Bernard Fischer getting hired.

Helen McAllister[]

First Appearance: Atomic Robo and the Deadly Art of Science

Helen is Jack Tarot's daughter. She is rather brash, speaks her mind easily, and is quick-tempered, but is very decisive and has quick and nimble fingers. As part of the vigilante duo, she serves as the mechanic, inventor, and intelligence-gatherer while Jack is out crime-fighting. To conceal her identity, she is codenamed Nightingale during missions when father and daughter communicate with each other.

When Robo insisted in joining their group, she was more than happy to welcome the automatic man into their adventures. This was a beginning of a romantic relationship between the two.

Frederick A. Mitchell-Hedges[]

First Appearance: Atomic Robo and the Deadly Art of Science

Frederick is a wealthy collector of artifacts residing in New York City. During one of the lab raids from the Chicago and New York outfits, a crystal skull of Atlantean origin he had in possession was stolen from him. He claims the police isn't taking the crime seriously, and this concerns him as he understands the power contained within the skull.