Terry Sloane was a rich man whose photographic memory, Olympic-level athletic skills, and mastery of the martial arts made him a virtual Renaissance man. After graduating college at age thirteen, he eventually became a renowned business leader in the community. Having accomplished all of his goals by the time he was in his early 20s, Terry felt there were no challenges left for him to pursue, leading him towards suicidal tendencies. However, upon seeing a young woman jump from a bridge, Sloane reacted quickly and saved her. He learned her name was Wanda Wilson. Sloane assisted her brother, who had been caught up in a gang, by adopting his Mister Terrific persona. He then created the "Fair Play Club" to stymie growing juvenile delinquency.
Sometimes nicknamed "The Man of 1,000 Talents," Terry Sloane turned to crimefighting after excelling at everything else. He wore a red suit with a green tunic. A golden emblem on his tunic proclaimed his motto, "Fair Play". Mister Terrific became a reserve member of the Justice Society of America, taking part in two of their chronicled 1940s adventures. He also was a full-fledged member of the All-Star Squadron and assisted both teams on several more occasions throughout the remaining decade, retiring along with his peers in 1951.
Sloane resumed his crimefighting career, at which point he was given full status as a member of the Justice Society. On several occasions he assisted them in various cases, such as combating the Lawless League and the Black Orb crime gang.
Sloane made an appearance in Justice League Year One, at the first gathering of the League. He was seen being looked after by Phantom Lady during a gathering of heroes on Blackhawk Island, after the final defeat of the alien Apellaxian army.
Sloane came out of retirement to pursue his old nemesis, the Spirit King. The Spirit King took control of the Golden Age Flash and used him to kill Sloane.
Sloane has appeared after his death in the afterlife and via time travel. About once a year, during the run of writer James Robinson's superhero title, Starman, title character Jack Knight had a supernatural visit from his deceased brother, David, under the recurring title "Talking With David". One year, David showed up with several other dead heroes, including Mister Terrific. They had a dinner party in the black-and-white realm. During his visits, the motivations for heroics and vigilantism were discussed.
Through time travel, Sloane and his successor, Michael Holt, have met. Sloane, Holt's JSA, and the Freedom Fighters of Sloane's time teamed up to stop a rampaging, highly destructive time traveler. In the past, the villain had already damaged many parts of Washington D.C., killing many, but they were able to defeat him when Sloane tricked the time traveller into thinking that he was the time traveller's ancestor, threatening to shoot himself before he could have any children to cut the other man's family history short (Although he later admitted that he was bluffing as it would be impossible to determine a family connection given the numerous generations between Sloane and the time traveller). Despite the JSA trying to be secretive, Sloane figured out much about their mission and methods.
Sloane made another post-death appearance in the Day of Judgement series. A team of heroes attempted to break into Heaven in order to persuade Jim Corrigan to retake the mantle of the Spectre. Sloane and other dead heroes appeared to try and gently dissuade the heroes from their mission.
Sloane joined forces with Holt once again when time-traveler Per Degaton launched an attack on the JSA in 1951 with the intention of framing the now-disbanded team for the destruction of Washington and the death of the President of the United States. Time-traveler Rip Hunter was able to prevent this by recruiting key members of the future JSA to recruit their more troubled predecessors to take action, Holt learning more about Sloane's family history during his time in the past (Including his potential ties to Holt's future foe Roulette).
During the Blackest Night crossover, Sloane is reanimated as a member of the Black Lantern Corps. He is one of many JSA-associated Black Lanterns to attack the current JSA in New York City. The corpses are destroyed by a unique device created by the current Mr. Terrific.
A version of Terry Sloane calling himself 'Terry Sloan' appears in The New 52 version of Earth-2. He attacks Michael Holt, the Mister Terrific of Earth-0 (the main DC Universe as of 2011), after he is teleported to Earth-2. It was confirmed during the 2012 San Diego Comic-Con International that Sloan will be featured as the Mister Terrific of Earth-2.
In issue 0 of Earth-2, Terry Sloane was revealed as one of Earth 2's original eight superheroes, a hyper-intelligent operative known as Mr. 8 who fell from grace after he destroyed areas the forces of Apokolips had invaded, and became his world's worst supervillain.Another version was portrayed in JSA: The Liberty File and its sequel JSA: The Unholy Three. Here, Terry Sloane was portrayed as a World War II intelligence agent transferred to desk duty, until the untimely death of his fiance by the story's version of the Scarecrow. He was seen wearing a variation of the classic "Fair Play" costume and using a rapier.
Sloane was mentioned in The Golden Age Elseworlds story as having retired from crime fighting and is now running an airline. Unconfimred rumors suggest he acquired this using underhanded tactics.
Terry Sloane had no superhuman powers but he was a master martial artist and an Olympic-level athlete with a genius-level intellect. He also possessed photographic memory allowing him to remember important clues and information.
The Golden Age Mister Terrific was said to be a favorite of author Michael Chabon, who contributed a story about Sloane to the JSA mini-series All-Stars in 2003. According to Chabon's story, Sloane was the protector of Gateway City. He had a brother, Ned, a butler named Butler, and a doorman named Smitty. In the Chabon story, Ned Sloane was portrayed as an alcoholic, compulsive gambler, who has the "power to hit bottom, and then, somehow, keep on falling".
It has been established that Terrific's brother Ned was the grandfather of the Modern Age criminal Roulette; however, in her original appearance she believed for unknown reasons that Terrific himself was her grandfather, and regarded the new Mister Terrific as a pretender to the role. In another time-travel adventure Michael Holt helps Sloane after he has abducted Ned's daughter from the original Roulette's lair, refusing to allow his niece to grow up in a den of gamblers. One can infer that he adopted her, thus Roulette assumes Sloane is her grandfather.
A character named Ms. Terrific was introduced in the 1989 series Hero Hotline as a member of the group's night shift team. Although her outfit was based on Terry Sloane's costume, it is unknown if she had any connection to him.
In Alan Moore's Top 10, in one scene, among a pile of knocked out people is a person that wears a costume that looks like Terry Sloane's, but has "Xtra Play" on his belt instead of "Fair Play".
Mr. Terrific is one of seven JSA-related heroes whose solo appearances are collected in an anthology entry in the DC Archive Editions series: