K the Unknown. Douglas Danville is a "wealthy playboy" who grew "bored with being a playboy" and put on a costume, becoming K the Unknown. He is "wanted by both police and underworld." He has no superpowers. His sweetie is private investigator Terry Dane, who doesn't know about Doug's secret identity and who wants to capture K.
First Appearance: Prize Comics #1 (Prize) Note: See also the Black Owl.

Kaanga. Kaanga is a white boy who is orphaned when his explorer family and other members of their expedition are slaughtered in the Congo. The boy, whose real name is never revealed, runs away and is adopted by a local tribe of “ape-men.” They raise him to be one of their own, and he grows up to be one of them, forgetting all he knew of the “white man’s ways and talk.” Sure enough, of course, as an adult he gets involved with some honkies who reteach him English. He falls in love with one of them, Ann Mason, and the pair marry and live, Tarzan-and-Jane-like, in the jungle, fighting for good against everything from bad animals to dinosaurs to witch doctors to Germans.
First Appearance: Jungle Comics #1 (Fiction House)

Kalthar. To quote from his first appearance:

Kalthar is a white man, wild and cunning, and strong as the beasts whose language he speaks. He has been reared from infancy by savage blacks, the Ugarnas, who were rescued from Arab slavers by Kalthar's father. Freeing the Urganas, Kalthar's father lost his own life. The fleeing blacks took with them his boy child and called him Kal-Thar, or God-son.

Kangaroo Man. Bingo the Kangaroo is a touring kanga who somehow has the intelligence and personality of a human being. With his trainer Jack Brian he tours Australia and America, fighting the Germans. Bingo has human-level intelligence, is good (of course) with his fists and feet, and can even drive a motorcycle.
First Appearance: Choice Comics #1 (Great Publications)

Kardak. Kardak, says Michael Norwitz, is a "Mandrake-type magician."
First Appearance: Top-Notch Comics #1 (Archie)

Kato. Kato is the Filipino valet of the Green Hornet and helps him fight crime. Kato has no superpowers but is an expert martial artist.
First Appearance: Green Hornet Comics #1 (Harvey)

Kay McKay. "Kay McKay, an air hostess on 'World Wide Airlines,' carries out her duties with intelligence and courage. She also has the knack of getting in and out of trouble." Interestingly, she is based in Mexico City.
First Appearance: Banner #3 (Ace Periodicals)

Kayo Kane. Rod Kane is a logger for the Northmill Lumber Company who is a good boxer, hence his name. He is very strong and is helped by his best friend Mason.
First Appearance: All New Comics #1 (Family/Harvey)

Kayo Kirby. Red “Kayo” Kirby fights his way up out of humble beginnings to become a top prize fighter, slugging his opponents and criminals alike.
First Appearance: Fight Comics #1 (Fiction House)

Ka-Zar. David Rand is...heck, let's be honest, he's a pretty transparent Tarzan clone, fighting evil in the jungle with his lion friend Zar. His father, John Rand, "young owner of a rich diamond field in the Transvaal," is flying to Cairo from Johannesburg with his wife Constance and son David when the plane develops motor trouble and is forced down in the "thick, wild TROPICAL FOREST!!" of the Belgian Congo. John and Constance die soon afterwards, from a "raging fever" and a broken heart, leaving David alone to raise himself. When he's a young adult, similar in skills and dress to Tarzan (go figure), he becomes friends with the elephant Trajah and with the lion Zar, the "lord of the jungle," after saving Zar from quicksand. (He later befriends Sha, Zar's mate) His skills are of the Tarzan variety. Interestingly, in most issues he has no superpowers, but in Marvel Mystery #26 he is given a brew by a witch-doctor which grants him enhanced strength and endurance.
First Appearance: Marvel Comics #1 (Timely)

Ken Keen. Captain Ken Keen is a heroic member of the Planet Patrol, which keeps the peace in the solar system at some point in the far future. He has a spaceship and a blaster. He's helped by "Nirma, the Martian beauty."
First Appearance: Silver Streak Comics #3 (Lev Gleason)

Kenny Carr. Kenny Carr is a British Captain in the "Martian Lancers." The strip essentially transplants all those stories of the "British Lancers" in India to Mars, with the Martians taking the place of the enemy Sikhs/Afghanis, down to wearing turbans. The strip is quite low-tech despite being on Mars in the future, and Kenny is a typical British soldier hero.
First Appearance: Planet Comics #3 (Fiction House)

Kid Cobra. Bob Hornsby puts on a costume, sidekicks for his older brother, Jim , aka Black Cobra, and fights crime. He has no superpowers.
First Appearance: Dynamic Comics #1 (Dynamic) Note: The rights to the Kid Cobra were later picked up by Four Star Publications, and the character appeared in Four Star's Captain Flight Comics.

Kid Colt. Blaine Colt trained himself from childhood to become an expert with the gun that bore his name, but never used it for fear of giving in to his temper and hurting someone. Blaine's father, Dan Colt, is indeed disappointed in his son, who in his ignorance thinks that Blaine is soft and perhaps a coward. Dan is the owner of the Flying-C Ranch outside of Abiline, Wyoming; when he tries to oppose Lash Larribee, the head of the "Ranchers Protection Association," Larribee shoots him down. Blaine, furious, straps on his Colts, stalks into town, outdraws Larribee and kills him. Larribee's men accused Blaine of murdering Larribee, and Blaine went on the run, becoming the itinerant cowboy do-gooder known as Kid Colt.
First Appearance: Kid Colt #1 (Timely)

Kid Dixon. Kid is a crime-fighting boxer aided by his manager, Bottle Topps.
First Appearance: National Comics #1 (Quality)

Kid Eternity. The nameless Kid is working on his grandfather's merchant marine ship when it is hit and sunk by a U-boat's torpedo. On getting to heaven, however, the Kid is met by the angelic Mr. Keeper, who tells him that he was supposed to live another 75 years and that his death was an accidents. Mr. Keeper accompanies the Kid back to Earth and by way of apology gives him an exceptional power, to be able to summon up anyone from "mythology or history" with the word "Eternity." The Kid, back on Earth, can now make himself solid, too, and with the help of people like Sir Launcelot and Merlin fights against crime, evil, and the Germans.
First Appearance: Hit Comics #25 (Quality)

King (I). King Standish is a millionaire playboy and sworn enemy of crime. He has no superpowers, but is a master of disguise, enough to continually fool the criminals into believing that the person they are confiding in is not the King, and is an ace locksmith and marksman. He is initially opposed by and then later helped by the Witch, his "loving enemy" who he convinces to turn to the good.
First Appearance: Flash Comics #3 (DC)

King (II). Sir Oliver King is a rich English adventurer and detective who goes to Singapore to retrieve his long-lost son Roger and then returns to Liverpool, fighting crime in both cities and on the ship that carried him.
First Appearance: The Arrow #1 (Centaur)

King Carter. King Carter is a two-fisted explorer, globe-trotting adventurer, and soldier of fortune. He is helped by Red Rogers, his best friend and an above-average pilot.
First Appearance: More Fun Comics #49 (Quality)

Kit. Kit is the sidekick of Cat-Man. He has no superpowers but possesses and uses a wide range of inventions.
First Appearance: Cat-Man Comics #1

Kitten. Katie Conn is an eleven-year-old girl whose parents are killed in a train wreck. She is adopted by David Merrywether, aka Cat-Man. Katie is already a trained acrobat, so it's a relatively simple thing to train her to fight crime and then make her his sidekick. He puts her in a cat costume and calls her Kitten, and she helps him. As time goes by she amply develops, and their relationship takes on some odd overtones. She is also a member of the Little Leaders. She is a good fighter and acrobat, but has no superpowers.
First Appearance: Catman Comics #5 (Holyoke)

Kitty Kelly. Jakeoster contributes the following:

Kitty was a costumed heroine with super-strength. Her costume was red with a "KK" emblem on her chest, and a blue cape. Note: Other appearances of the "Kitty Kelly" strip feature her as an airline hostess. To further confuse matters, Kitty Kelly may also have been the alias for Yankee Girl (Captain Flight # 8, May 1945). The same publisher later came up with a second Yankee Girl in Dynamic Comics # 23 (Nov 1947).

Kon Fu. Dr. Kon Fu is a "master of Oriental and Occidental Cultures" and "stands bravely between his people and oppression--defying even monsters of evil magic." He is young and Chinese, living in San Francisco's Chinatown. He is a master of the martial arts and has a hidden cellar wherein lies his "Temple of Magic." In the Temple is a statue of the "Green Goddess," and when the Goddess is prayed to--by, say, her servant and worshiper Dr. Kon Fu--she will come alive and dispense advise.
First Appearance: Doc Savage Comics #1 (Street and Smith)

K-4. Captain K-4 is the leader of the Sky-Devils. K-4 is a "flying spy and soldier of fortune" who had 11 victories in WW1, "triple that with the loyalists in the Spanish rebellion, and dozens more in the China-Japan conflict." He has no superpowers but is an ace in his Grumman and a dreaded foe of the Germans.
First Appearance: Daring Mystery Comics #2. (Timely)

K-51. K-51 is an American spy active in Occupied Europe fighting the Germans.
First Appearance: Wonderworld #3 (Fox Features)

Introduction
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