Masatoshi Nagase is primarily known as a celebrated live-action film actor who has occasionally taken on voice acting roles in anime and animated films. Born on July 15, 1966, in Miyazaki Prefecture, Japan, he made his entertainment debut in 1983 with the film Shonben Rider. While his career has largely been defined by his work in cinema, his contributions as a voice actor include a handful of notable projects.

Nagase's most widely recognized voice role is in the long-running detective series Case Closed, known in Japanese as Detective Conan. He voiced the character Hamike, also referred to as Mike Hama. This role connects to his broader association with the character of Mike Hama, a private detective he portrayed in live-action television dramas, making the voice cameo an extension of that persona. His earliest voice credit dates back to 1983, when he provided the voice for a character in the anime film Miyuki, marking his first foray into voice work shortly after his screen debut. He also performed voice work for the animated film The Street Corner Story. In a departure from typical anime, he appeared in the 2002 live-action film Suicide Club, rather than an animated version of the story.

Throughout his career, Nagase has received numerous accolades for his live-action performances, which include winning the Japanese Academy Award for Best New Actor and Best Supporting Actor for the film My Sons. His international recognition grew with his role in Jim Jarmusch's film Mystery Train, and he continues to balance leading roles in Japanese cinema with appearances in international productions. While his work in anime is a smaller facet of his overall career, his distinct presence has made his limited voice roles noteworthy to audiences who primarily recognize him from film.