Glenn Cannon (November 21, 1932 – April 20, 2013) was a Hawaii-based actor and educator best known for his roles on Hawaii Five-O and Magnum, P.I. He also appeared on Lost in a pair of different roles. Cannon's career began back to the 1950s with roles in shows like Alfred Hitchcock Presents, The Outer Limits and Combat!. On Magnum, P.I., Cannon was featured as Dr. Ibold, while on Hawaii Five-O, he played Attorney General John Manicote. In the mid-1960s he taught elementary school in Los Angeles at Lanai Road School in Encino, California.In recent years, he served as president of the Hawaii chapter of the Screen Actors Guild and its successor group, SAG-AFTRA.Cannon was a Professor of Theatre at the University of Hawaii at Manoa and also co-Director of the UH-Manoa Cinematic and Digital Arts program.