Captain Steve "Jetman" Traynor, a tough but fair former Golden Age flyboy and closeted homosexual.
Detective John "King Peacock" Corbeau, a powerfully built adherent of the Yezidi faith, which many mischaracterize as "devil worship," which... it sort of is. He can commune with his god to discover the weaknesses in objects, allowing him to shatter them.
Detective Miriam "Synaesthesia" Jackson, whose synesthesia causes her sensory input to kind of mingle together and overlap. "I like her. She smells kind of like windchimes."
Lieutenant Cathy "Peregrine" Colby, a principled, bodybuilding born-again Christian with a flying harness.
Officer Alexei "Spaceman" Glushko, alcoholic Russian ex-Cosmonaut telepath and Special Interrogator for the precinct.
Officer Duane "Dust Devil" Bodine, a gold plated cowboy with custom twelve-shooters whose mother, a Living Lie Detector, has an Ultra-Mouse problem. Has actually never been further West than Chicago. He and Jackie like to flirt, even though they bat for the same team.
Officer Joe Pi, a Ferro-American and model officer who joins halfway through. His appearance is modeled after Japanese super robots - artist Gene Ha describes him as a mix of "Great Mazinger Zapper, Ultraman, Shogun Warriors, general bits of historic Japanese helmet design, but also Spectreman!"
Officer Robyn "Toybox" Slinger, a gadgeteer with a toy box filled with various things like armed mini helicopters and robots for surveillance, and weirdly enough it later turns out her box is in fact Pandora's box, so the last thing in it is hope.
Officer Sung "Girl One" Li, an Artificial Human martial artist who can't wear clothing but can change the color of her skin. Unlike the standard take on this trope, she actually has a nudity taboo, just a biological compulsion to stay nude built into her brain. Her "uniform" is simply her changing the color of her naked skin to form patterns, with its default being a light purple. Was somewhat upset when she learned Hyperdog was color blind.
Has (at least) two "sisters", Girl 54, who replaces her after she dies, and Girl Two, who tries to replace her in the meantime, but fails in her color shifting trick and is nearly raped during a hostage situation, causing her to leave the force and become a lawyer. An unnamed sister is seen helping bat-invaders in Beyond, whose stick was mostly a dark black starfield pattern.
Sergeant Hector "Monsoon" Lopez, a garishly-clad weather controller who mans the front desk at the station and tends to react to stressful situations with extreme deadpan.
Bill "Wolfspider" Bailey: The legless S.W.A.T. team who wears a spider-like suit of powered armor. He lost his legs in a teleporter accident. By the way, he's the only member of the S.W.A.T. team. He's that good.