Frank Oz was one of Jim Henson's closest creative partners, beginning in 1963. Oz played Bert to Henson's Ernie on Sesame Street, and he also performed Cookie Monster and Grover. In 1976, Oz created many of the core characters for The Muppet Show, including Miss Piggy, Fozzie Bear, Animal and Sam the Eagle, and he continued to perform these characters in the Muppet movies and TV specials. Henson and Oz collaborated on the 1982 film The Dark Crystal, directing as a team. In the mid-1980s…