Cinematographer Gregg Toland and Orson Welles had a reputation for being innovators as well as rebels against the system. While Toland was a consummate professional, he hated the relationship between the studios and the cinematographers. As a result, he also detested the flat cinematography most films possessed at the time. Fortunately, his lifelong career at Samuel Goldwyn Studios was the solution where everything he wanted was in the studio. At Goldwyn Studios, Toland succeeded in being nominated for four films including his work for "Wuthering Heights" in 1939, of which he won the award. His constant reinvention or modifying the equipment he had to experiment with camera and its sense of depth, eventually leading him to the technique of deep focus. With Welles, his reputation with the Mercury Theatre preceded him when he arrived in Hollywood. It was only fitting for these two rebels to make, what is considered "the greatest film ever made", "Citizen Kane" (1941).

In 1941, word around Hollywood was that RKO Studios secured a two-picture deal with an unknown director, Orson Welles. Toland was interested in working with Welles because, as he told Welles later, that he wanted to work with a director who did not know anything about the camera and was willing to learn. Toland thought it would be a pleasure to teach an amateaur than work with another director who knew everything about film. Fortunately for Toland, Welles was looking for a veteran cinematographer with Toland's background and hired Toland as his cinematographer. He was a loan-out to RKO for $700 a week.

When pre-production started, Welles was already in hot water with RKO, of whom did not like the figures of how much it would cost the studio. RKO insisted that the cameras would not start to roll until the budget was fixed but Welles and Toland knew a way around all of it. In telling the studio that they were shooting tests and listing the daily reports as "Orson Welles tests", they were able to start filming shots on the lot. However, by the time the studio caught on to what they were doing, RKO had no choice to allow them to continue shooting the film. Although the process was purely improvised, Toland wrote in his article "How I Broke The Rules in Citizen Kane" that "The photographic approch to "Citizen Kane" was planned and considered long before the first camera turned."

During the production, it was their innovative and rebellious nature that resulted in a smooth relationship between Toland and Welles. Welles would give Toland an idea and in turn, the intrepid cinematographer would come up with a gadget or two to rig to the equipment and use in the shot. Both were well aware of the fact that Welles' vision had an emphasis on realism with as little technical interference as possible. This provided a heavy reliance on deep focus cinematography and long takes, two techniques that would become a staple in Welles' future projects.

After the film was finished, Toland and Welles reflected on the experience with nothing but admiration for one another. In 1967, Orson Welles commented, "I've known only one great cameraman: Gregg Toland, who photographed 'Citizen Kane.'" It was as early as the releast of the film that Toland praised Welles in his article "The Motion Picture Cameraman", writing, "...He proved one of the most cooperative artists with whom it has been my privilege to work...Photographing Citizen Kane was indeed the most exciting professional adventure of my career."

When "Citizen Kane" (1941) was released to the public, it received positive reviews despite the threats William Randolph Hearst made about the film. It was nominated for nine Academy Awards, yet it only won one and it was for the "Best Writing" Oscar. Unfortunately for Toland, "Citizen Kane" would be his final nomination and his only collaboration with Welles.

"Citizen Kane"'s legacy has stood the test of time with the American Film Institute listing it as their #1 film on their "100 Years 100 Movies" list. However, it will always be the film someone either reveres or despises, depending on the person.