While serving as a barker at a Broadway theater in 1929, Reeves met three animators from Pat Sullivan Cartoon Studios, producer of Felix the Cat shorts. He begged for a job. As a result, he met and worked under pioneer film animator Otto Messmer, creator of Felix. Messmer was a genius, but Sullivan was reluctant to allow him to make cartoons with voices.

In November 1930 Reeves severed ties with Sullivan and joined Disney, who was beginning to earn a favorable reputation, where he earned $60 a week as an “apprentice cartoon animator.” In 1934 he was an “animator and apprentice story writer.”