Iwerks' studio quickly began accumulating new talent, such as animators Fred Kopietz, Irv Spence, Grim Natwick, and Chuck Jones (who worked at the Iwerks studio as a cel-washer before going on to inbetweening and then animating at the Leon Schlesinger studio). After the first two cartoons, the appearance of Flip the Frog gradually became less froglike. This was done under the encouragement of MGM, who thought that the series would sell better if the character were more humanized. Flip's major redesign is attributed to Grim Natwick, who made a name for himself at the Fleischer Studios with the creation of Betty Boop. Natwick also had a hand in changing Flip's girlfriend. In earlier films, she was consistently a cat, but Natwick made Flip's new girlfriend, Fifi, a human who shared distinct similarities with Betty (even down to her spit curls).