THE PORTILLO EXPEDITION: MYSTERY ON BOUGAINVILLE ISLAND follows a crew of American explorers, assembled by Chicago restaurateur Richard Portillo, to a remote Pacific island in the western Solomon Islands. The crew's mission is to visit the site of many brutal battles fought during World War II, and to locate the wreckage from the plane carrying infamous Japanese Admiral Isoroku Yamamoto, the architect of the Pearl Harbor attack and the Battle of Midway. Yamamoto's bomber was intercepted and shot down by American P-38 fighter planes on April 18, 1943 in a top-secret mission accomplished by the breaking of Japanese naval code. The assassination of Admiral Yamamoto was a bold decision that changed the outcome of the war in the Pacific. On Bougainville Island, in the oozing mud surrounding the wreck of the admiral's plane, Portillo expedition leader and historian Andy Giles makes an incredible discovery: a gold tooth. Several factors indicate it could be Admiral Yamamoto's gold crown, discovered more than seven decades later. Portillo and Giles set out to determine if the tooth can be authenticated. The answer could challenge the generally accepted story in Japan that Yamamoto's body was discovered in a pristine state, complete with white gloves and sword. Narrated by actor Gary Sinise, THE PORTILLO EXPEDITION traces the remarkable search for answers that took the team from the jungles of Bougainville to the offices of DNA experts in the U.S., and finally to Yamamoto's home city of Nagaoka, Japan.