As an artist

He was inspired by bands Hikaru Genji and SMAP to answer a recruiting call of Johnny & Associates and was accepted in 1990. In 1992, he played several stage plays (Playzone and Mask) together with other Tokio members. He first played tambourine during Tokio's early performances as SMAP's background dancers. Just prior to Tokio's debut, the band's rhythm guitarist, Hiromu Kojima, left the band and was replaced by Tomoya Nagase.

In 1997, Nagase collaborated with American R&B group 3T to record the Japanese version of Eternal Flame, which was used as the theme song for the Japanese drama D×D, in which he starred. The single was released under the artist name "Tomoya with 3T" and reached number 12 on the Oricon charts. Nagase lists Guns N' Roses as his favorite band.^[4][5]

In July 2020 it was announced that Nagase will be leaving Johnny & Associates in 2021.^[6]

In June 6, 2023, Nagase released an album with his new band, Kode Talkers, through Challenger Records. The album is titled the same as the band name. Nagase is the lead vocalist and guitarist along with Kotaro Kubota, who also does chorus/back vocals. An artist named Fire does the bass and back vocals; Kiyohide Ura on keyboard; and Daiki Nakahata on drums are the rest of the band. On the album, there are nine songs: 情熱のグルーブ; 例のモノ; When I; ハンディキャンディマン; Wonder; どっかに置いといて; 脱力の法則; 帯電Youthful; Free Wheelers.^[7]

As an actor

Nagase has had parts in over 40 dramas. His first lead role was in Hakusen Nagashi (1996). More lead roles followed including Ikebukuro West Gate Park, Mukodono!, Unubore Deka, and Tiger & Dragon. Mukodono! was his first comedic role. In My Boss My Hero he had another comedic role. He received an "Ishihara Yuijiro Award" in 2002 as "The Best Newcomer" for his role in the movie Seoul.

Endorsements

Nagase has endorsed many various brands with the band Tokio and by himself. He is currently a brand ambassador for Fujicolor and Lotte Toppo. With Tokio, he has endorsed among others Microsoft's Xbox 360 and Eneos, a brand for Nippon Oil. As an actor, he has also endorsed UFO Nissin noodles, Lotte Coolish drinks, Subaru, Morinaga, Suntory Dry beer, Mazda, All Nippon Airways, NTT docomo, Hitachi Wooo, and Uniqlo.