Simon's most famous saying was, "Simon says!" His henchman was Cad Lackey, who, though generally dull-witted, was occasionally capable of pointing out flaws in his boss's plans. Contrary to the mad scientiststereotype, Simon actually paid attention to Cad's suggestions.
In the 2007 live-action film adaptation, he is portrayed by Peter Dinklage. In the movie, Bar Sinister was originally a geneticist for a company in Capital City, using dogs as test subjects for the betterment of mankind. But after being laughed at by the mayor after attempting to have his research expanded to law enforcement, Bar Sinister began his work to create a super-power formula to get revenge and he took away Underdog's superpowers and put them in little blue pills and fed them to German shepherds and was sent to jail for his crimes. However, the incident resulted in the destruction of his lab that not only caused scarring of his forehead, the loss of some of his hair, and a limp in his right leg, but created Underdog.
"Bar Sinister" is a macaronic reference to a heraldic mark, called barre sinister in French and bend sinister in English. The bend sinister is a line from the top right to the bottom left, and its diminutive form, correctly called a baton sinister, denotes illegitimacy. Despite its heraldic inaccuracy, the term bar sinister has been used in literary contexts to denote bastardy since the early 19th century. Hence, the name Simon Bar Sinister could be translated as "Simon the Bastard".
Episodes in which he is prominent
"Simon Says" (first appearance): Invents a camera used to freeze living things in photographs.
"Go Snow": Invents the Snow Gun to turn people into snowmen and snowwomen. After he snowed Underdog into submission, Underdog managed to defrost himself and then flew around in circles, making Simon and Cad too dizzy to continue their plan.
"The Big Shrink": Desires to be the biggest man in the world, so he invents Pure Distilled Shrinking Water to shrink people to the size of his thumb. After using the shrinking chemical on Underdog and Sweet Polly, he uses his Rainmaking Machine to make it rain Shrinking Water all over the city, and he even shrinks Cad. Underdog, Polly and the townspeople shrink him to the size of a flea and tickle him into telling them the cure to the shrinking water. After Simon tells the townspeople the cure, he and Cad are sent to jail.
"Weathering the Storm": Invents the Weather Machine to distort the Earth's weather patterns, but finds out he can't use the Weather Machine against Earth if he's on Earth. Cad points out they could use the Weather Machine if they weren't on the Earth. Simon and Cad spoil the Moon launch at Cape Canaveral by stealing a spacecraft with Sweet Polly as their prisoner after incapacitating the astronauts who were supposed to go with Sweet Polly. Sensing the danger, General Brainley, in charge of organizing the Moon launch, sent word for Underdog. Simon warns that if Underdog were to go to the moon, to harm Simon, Sweet Polly would be harmed. While Simon demonstrates the Weather Machine's powers, he creates a flood, which floods the Capitol Building, but Underdog makes a built-in drain, sending the flood out to sea. Then, Simon creates a lightning storm, but Underdog throws the lightning bolt into the sky. Then, Simon tries a tornado, but Underdog stops it with his atomic breath. Simon, after listening to one of Cad's suggestions, threatens to press all the keys on his Weather Machine unless the Earth agrees to make Simon dictator, and the world leaders have one hour to decide. Underdog knew it would be impossible for him to stop tornados, earthquakes, floods, hurricanes and many other natural disasters all at once, and even if Simon spotted Underdog nearing the Moon, he would press all the keys on the Weather Machine and destroy the Earth, with Sweet Polly, too. Underdog turns invisible and defeats Simon and Cad, destroys the Weather Machine, rescues Sweet Polly and returns Simon, Cad, Polly, and the spaceship to Earth where Simon and Cad will be sent to jail.
"The Phoney Booths": Replaces phone booths with Phoney Booths to brainwash people who use the booths. Underdog is also the victim of Simon Bar Sinister's phoney booths, but Underdog overcomes Simon's power, and destroys Simon's evil phone booths and Simon and Cad are once again sent to jail.
"The Forget-Me-Net": Invents a net to erase the memories of others. He planned to use the net on Underdog by robbing a jewelry store and a toy store, but Underdog was busy taming a typhoon and stopping a band of pirates. So, he decides to kidnap Sweet Polly and use the net on Underdog, erasing Polly's memory in the process. After using the net on Underdog, he realizes the cure to the net's effects is if the victim hears his or her name, so he disguises Underdog as an elderly woman who sells apples, and then plans to erase the memories of all the people in Washington D.C. Underdog and Polly regain their memories and stop Simon and Cad by using the Forget-Me-Net against them, causing both Simon and Cad to forget who they are.
"Simon Says 'No Thanksgiving ' ": He plans to make himself master of the city with an army consisting of 3 airplanes, 3 tanks and 12 soldiers. Sweet Polly overheard it and the police that she informed of this laughed at the fact of Simon using 3 airplanes, 3 tanks, and 12 soldiers. He planned it on the same day of the Thanksgiving Day parade and was disappointed at that. Cad points out if Simon's plan fails, he and Cad will be laughingstocks of the city. So he plans to go back in time and destroy Thanksgiving by having the Indians fight the Pilgrims. With that done, he'll be able to push the buttons on Main Street locking every door in the city and he'll be able to carry out his plan. Underdog and Polly as usual foiled his plan. When his army started the attack, they were quickly arrested and Simon was the laughingstock of the city.
"The Tickle Feather Machine": After the narrator makes reference to Simon's previous failed inventions to conquer the world (the Shrinking Water, the Weather Machine, the Snow Gun and the Forget-Me-Net, respectively), Simon decides to run for dictator, but quickly realizes nobody will vote for him since he's the most wicked person in the world. So Simon and Cad must vote for Simon themselves and prevent others from voting. He invents the Tickle Feather Machine to make people laugh so hard, they won't vote against him. After firing the Tickle Feather on Underdog and Sweet Polly, he and Cad vote for him for dictator and threatened a cook, a banker, a construction worker, and Sweet Polly to do whatever he says. It may look as though Simon was legally elected, but he wasn't. Underdog found info that Sweet Polly revealed on the television like Simon Bar Sinister and Cad are convicted criminals and they weren't registered to vote. This caused those that Simon threatened with the Tickle Feather Machine to turn against him as Underdog disposes of the Tickle Feathers.
"The Big Dipper": Invents the Big Dipper Machine to steal every water reservoir in the world, including oceans, seas, lakes, rivers, lagoons, ponds, and swimming pools. Underdog stops Simon from dipping all the water in the world, and Underdog restores all the water to everybody, and Simon and Cad are sent to jail again.
"Simon Says 'Be My Valentine ' ": Uses his Valentine Vault to turn others into Valentine cards. Simon and his thugs intended to use the Valentine Vault on Underdog, but first they needed Sweet Polly as the bait. When Underdog arrived to rescue Polly, he was turned into a Valentine that Simon was going to use for a dartboard. When Simon and his thugs left the lab to use the Valentine Vault on the Mayor and the City's Officials, Underdog broke free of his Valentine Prison using his Super Energy Pill and rescued Sweet Polly. Simon and his gang were eventually defeated and turned into Valentine Cards themselves.
"The Vacuum Gun": Enlists the help of Batty-Man, Riff Raff, Electric Eel, and the gangs that each one led to pull crimes all over the world. Underdog managed to defeat them all.
Simon's diabolical machines
Air Raid Sirens
"Simon Says 'No Thanksgiving'"
Located on Main Street. Simon and Cad used these to send the citizens of the city into their homes so Simon and Cad can lock them in the buildings and dominate the city.
Big Dipper Machine
"The Big Dipper"
To steal the world's water supply.
To freeze its victims into photographs. When the victims of the ray are turned into photographs, the only way to reverse the process is to switch the direction of the camera lens.
"The Forget-Me-Net" "The Tickle Feather Machine"
A net used to erase the memories of others. The cure to the net's effects is as if the victim hears his/her name. The narrator makes reference of this weapon at the beginning of the episode "The Tickle Feather Machine".
"The Phoney Booths"
Simon replaced all the telephone booths in the country with these fake telephone booths. Those who use these telephone booths will be brainwashed into doing Simon's bidding.
Pure Distilled Shrinking Water
"The Big Shrink" "The Tickle Feather Machine"
To shrink its victims to the size of Simon's thumb. Simon intended to use it to shrink everyone in the world, but Underdog and Sweet Polly, after shrinking Simon to the size of a flea, tickled Simon into telling them the antidote to the Shrinking Water at which point Simon and Cad were sent to prison. The narrator makes reference of this weapon at the beginning of the episode "The Tickle Feather Machine".
"The Big Shrink"
It creates rain clouds. Simon used this to make it rain shrinking water on the citizens of the city.
"Go Snow" "The Tickle Feather Machine"
To turn people into snowmen and snowwomen. After he snowed Underdog into submission, Underdog managed to defrost himself and then, flew around in circles, until Simon and Cad's plan was foiled. The narrator makes reference of this weapon at the beginning of the episode "The Tickle Feather Machine".
"The Big Shrink"
The traditional stunt clowns use. Simon filled this Squirting Flower with his Shrinking Water. He claims filling the Squirting Flower with Shrinking Water is far more artistic.
Tickle Feather Machine
"The Tickle Feather Machine"
To tickle the country's citizens so they'll be unable to vote against Simon. That way, Simon and Cad can elect Simon as dictator.
"Simon Says 'No Thanksgiving'"
To travel in time so he can destroy Thanksgiving. That way, Simon can make himself master of the city with an army of 3 airplanes, 3 tanks and 12 soldiers.
"The Vacuum Gun"
To "clean out" crime. Simon used it to recruit Batty-Man, Electric Eel, Riff-Raff, and the gangs that each one leads in order to pull off a crime-spree across the country.
"Simon Says 'Be My Valentine'"
To transform those who enter the vault into a Valentine Card.
"Weathering the Storm" "The Tickle Feather Machine"
The Weather Machine's designs are similar to a pipe organ. Simon used it to distort the Earth's weather patterns, but finds out he can't use the Weather Machine against Earth if he's on Earth. Cad points out they could find a spot that wasn't on the Earth so they could use the Weather Machine. Simon and Cad, with Sweet Polly captive, use the Weather Machine on the Moon, but Underdog destroys it, rescues Sweet Polly and returns the stolen spacecraft to Earth at which point Simon and Cad are arrested by the military police. The narrator makes reference of this weapon at the beginning of the episode "The Tickle Feather Machine", only that time, its designs were similar to a ray gun.