 Michael Jackson , a former Motown star who by the start of development on The Wiz in 1977 , had left Motown for Epic Records with his brothers The Jacksons , was cast as the Scarecrow . Jackson was dedicated to the role , and watched videotapes of gazelles , cheetahs , and panthers in order to learn graceful movements for his part . Ted Ross and Mabel King were brought in to reprise their respective roles from the stage musical , while Nipsey Russell was cast as the Tin Man . Lena Horne , mother @-@ in @-@ law to Sidney Lumet during the time of production , was cast as Glinda the Good Witch , and comedian Richard Pryor portrayed The Wiz . 
