Shin Nagai, also known as Arata Nagai, is a Japanese voice actor born on October 3, 1997, in Hyogo Prefecture. He is affiliated with the talent agency m&i and is a graduate of the Mausu Promotion Actor Training Center. His journey into voice acting began during his school years, inspired by his participation in storytelling activities for children, which sparked his passion for performance.

Nagai's professional career started in 2015, with early roles in various television anime, web animations, and video games. His initial anime appearances included minor roles in series such as Goblin Slayer, Uzaki-chan Wants to Hang Out!, and Shadows House. His breakthrough came in 2021 when he landed his first main character role as Kimihiko Kimizuka in the anime television series The Detective Is Already Dead. This role brought him significant recognition and marked a turning point in his career. On January 1, 2021, he joined his current agency, m&i, and at that time, he changed the reading of his name from Shin Nagai to Arata Nagai.

Beyond this signature role, Nagai has contributed his voice to a range of other projects, including video games such as Monsters Strike, Destiny Child, Ryū ga Gotoku ONLINE, and World Flipper. He has also been involved in narration work for audiobooks and provided voices for educational materials and digital comics.

Known for his cheerful personality and natural Kansai dialect, Nagai has several hobbies and areas of expertise that are publicly documented. He enjoys playing the guitar and watching American football, and he specializes in playing the saxophone and football. He is also a certified Sake Navigator with beginner and intermediate certification in sake knowledge, reflecting his deep interest in Japanese sake. This passion even led to his participation in the sake-themed character project Miki no Mikoto. His approachable and friendly nature has earned him the nickname Shinshin among fans and colleagues.