While on a trip to Africa, he was bitten by a cobra and was saved by a transfusion of mongoose blood and soon discovered he developed super-speed. After returning home, he decided to become a crime-fighter. During World War II, Bucky (James Barnes) invited Robert to join the Liberty Legion and rescue the Invaders, who had been brainwashed by the Red Skull. When the Liberty Legion and Invaders eventually disbanded after the war, the Whizzer joined the newly-formed All-Winners Squad. Years later, the Whizzer reappeared as an aging hero who married the super-heroine, Miss America. He briefly served with the Avengers, who aided him in controlling his son, Nuklo. After being defeated by the super villain Count Nefaria, Robert decided to retire. He later returned to fight a final battle against an old war-time foe called Isbisa. The Whizzer died fighting Isbisa, but his sacrifice enabled Nuklo to begin a normal life.