Updated: April 15, 2022

In June 1951, Reeves was offered the role of Superman in a new television series titled Adventures of Superman. He was initially reluctant to take the role because, like many actors of his time, he considered television unimportant and believed few would see his work. The half-hour films were shot on tight schedules; at least two shows were made every six days. According to commentaries on the Adventures of Superman DVD sets, multiple scripts would be filmed simultaneously to take advantage of the standing sets, so that, e.g., all the "Perry White's office" scenes for three or four episodes would be shot the same day and the various "apartment" scenes would be done consecutively.

Reeves' career as Superman had begun with Superman and the Mole Men, a film intended both as a B-picture and as the pilot for the TV series. Immediately after completing it, Reeves and the crew began production of the first season's episodes, all shot over 13 weeks in the summer of 1951. The series went on the air the following year, and Reeves was amazed at becoming a national celebrity. In 1952, the struggling ABC Network purchased the show for national broadcast, which gave him greater visibility.

The Superman cast members had restrictive contracts which prevented them from taking other work that might interfere with the series. Except for the second season, the Superman schedule was brief (13 shows shot two per week, a total of seven weeks out of a year), but all had a "30-day clause", which meant that the producers could demand their exclusive services for a new season on four weeks' notice. This prevented long-term work on major films with long schedules, stage plays which might lead to a lengthy run, or any other series work.

Reeves, however, had earnings from personal appearances beyond his meager salary, and his affection for his young fans was genuine. Reeves took his role model status seriously, avoiding cigarettes where children could see him and eventually quitting smoking. He kept his private life discreet. Nevertheless, he had a romantic relationship with a married ex-showgirl eight years his senior, Toni Mannix, wife of Metro-Goldwyn-Mayer general manager Eddie Mannix.

In the documentary Look, Up in the Sky: The Amazing Story of Superman, Jack Larson described how when he first met Reeves he told him that he enjoyed his performance in So Proudly We Hail! According to Larson, Reeves said that if Mark Sandrich had not died, he would not be there in "this monkey suit". Larson said it was the only time he heard Reeves say anything negative about being Superman.

Between the first and second seasons of Superman, Reeves got sporadic acting assignments in one-shot TV anthology programs and in two feature films, Forever Female (1953) and Fritz Lang's The Blue Gardenia (1953), but by the time the series was airing nationwide, Reeves found himself so associated with Superman and Clark Kent that it was difficult for him to find other roles.