Doctor Roger Kadar is a scientist working in Charleston, South Carolina.
Dr. Kadar taught nuclear engineering at the University of South Carolina before the war. Sometime after the invasion, Arthur Manchester found Dr. Kadar and struck a deal with him to run Charleston's power grid.
Anne Glass comes to Kadar and asks him to devise a way to test the DNA of de-harnessed kids (and unknown to Kadar, Anne's baby Alexis) for any abnormalities. The doctor is able to run tests and finds that all the de-harnessed kids are healthy, but Alexis is not. Kadar discovered that Alexis's DNA is combined with alien DNA. When he talks to Anne about reporting Alexis's problem, Anne knocks him out.
Kadar explains to Vice President Marina, the Masons, and Captain Weaver what happened with Anne. He reveals to them the hybrid nature of Alexis. Later, Marina finds him running test for Lourdes to check the humaness of the other babies born in Charleston. She gives him photographs of the Volm "cannon", asking him to determine what it will be used for. After studying the pictures, he concludes that it is "overkill", saying that it stores more energy than is necessary for the plasma armature of the machine. He implies that there is something not quite right about the machine.
Kadar was underground when the bomb went off. He was crawling through a vent when he was surprised by Tom and Anthony, who were surprised to see him. Later, he and Tom were looking over blueprints, when he noticed a fire stairwell, which he noted was all reinforced concrete. He said he’d need a shaped charge about seven feet from the floor if they had any chance of getting through. He said he’d need 200 ft. of wire, when Anthony asked where to get it, Kadar said from the no longer functioning power lines in the walls. Tom began knocking holes in the wall to get to them. He told Anthony he would also need gunpowder from a dozen rounds, duct tape, any batteries he could find and some peanut butter because he was hungry. As he set the charges he noticed a crack in the support beam over his head. He said it may be a problem depending on whether its load bearing capacity had been compromised. Kadar said the charge may get through to the stairwell or collapse the ceiling and bury them in rubble. He then told Tom they’d have to move to another location. When Anthony noticed the beam held, he agreed saying low probability events do happen. He then helped Jeanne outside.
During the Second Assault on Boston, Kadar accompanied Tom’s team. He felt that after adjusting to the symbology the Volm language was intuitive and elegant. Tom came to check on him, Kadar felt he was learning quickly and estimated a 94% probability that the cannon would operate as expected. Kadar later manned the controls of the cannon with Cochise and informed Tom they were ready. On Tom’s order he and Cochise fired the cannon; the shot hit on the right-most leg. After the Beamers were shot down, Matt was the first to notice the Mothership was collapsing, Kadar cheered with the others as it did. Matt put the sunglasses back on and watched as the Grid deactivated and he informed the others. Tom congratulated Cochise and Kadar, who admitted it wasn’t what he expected. That night Dr. Kadar celebrated with the others. As they were leaving the city, Lyle walked with Kadar, asking if he was happy they weren’t going to the jungle. He wasn’t because of all the bugs there were in the woods. Sometime later Kadar asked Tom about Anne, he told Kadar she’s been sleeping a lot. Kadar felt that was to be expected and asked if she remembered anything while in captivity. She didn’t and he didn’t know if there wasn't any sign of an eye worm. When questioned about Lexie’s appearance Kadar felt her DNA suggested such a thing would happen. Tom wondered if this meant she would keep growing; Kadar told him it wasn’t possible to guess. Kadar tried to reassure Tom that maybe Anne could shed some light on what happened to them when she wakes up.
When the 2nd Mass was returning to Charleston after 22 days, the Espheni attacked, deploying Mega-Mechs, Beamers, and Obelisks. With the 2nd Mass separated, Kadar ended up in Chinatown with Lexi, Ben, Lourdes, and Maggie. During her accelerated growth Kadar took care of her and grew increasingly worried about her growth. He informs Ben that because of her accelerated growth she is dying. He later takes a blood test of Lexi, but the blood is destroyed and vaporises before he can test it.
After Lexi passes out, Roger rushes to her side. After taking her temperature, he is shocked after looking at it, as it shows that her temperature is 118 degrees. Anne asks him how is it possible, and in response he says it's not, as anything over 108 would cause the body to shut down and the proteins melting away.
|Season 3 appearances|
|On Thin Ice||Collateral Damage||Badlands||At All Costs||Search and Recover|
|Be Silent and Come Out||The Pickett Line||Strange Brew||Journey to Xilbalba||Brazil|
|Season 4 appearances|
|Ghost in the Machine||The Eye||Exodus||Evolve or Die||Mind Wars||Door Number Three|
|Saturday Night Massacre||A Thing With Feathers||Til Death Do Us Part||Drawing Straws||Space Oddity||Shoot the Moon|
- Dr. Kadar suffers from agoraphobia, which is a fear of going outside. He also has Asperger's Syndrome which explains why he's anti-social and why he doesn't like to leave his laboratory.
- It is highly indicated that Kadar lost a child during the invasion. (At All Costs)