Shimono, a Japanese-American, was born the son of restaurant owners Edith Mary, née Otani, and Masauchi Shimono. Shimono is the twin brother of Dr. Jiro Shimono, director of the Delaware Psychiatric Center, and a graduate of the University of California, Berkeley.
Shimono is an accomplished stage actor, having appeared on Broadway and in regional theaters including San Francisco's American Conservatory Theater and Berkeley Repertory Theater. One of his more memorable roles was as Hiroshi Kawamura in the 1990 drama Come See the Paradise and he also had a role in the 2008 independent film Americanese.
Shimono played a Korean spy on the popular, long-running TV series M*A*S*H, provided the voices for antique shop owner/Chi Wizard Uncle Chan on the hit TV series Jackie Chan Adventures, and played the Emperor, Jack's father, in the hit TV series Samurai Jack.
1984: Won a CLIO Award (Best Actor in a Commercial)