# Issei Mamehara

Issei Mamehara (豆原 一成, Mamehara Issei, born May 30, 2002), is a Japanese singer and actor. He debuted as a member of the Japanese boy band JO1 in 2020, after placing first in the first season of Produce 101 Japan. He made his debut as an actor in 2021 and played Kamen Rider Chimera in the Kamen Rider Revice films.

## Early life and education

Issei Mamehara was born on May 30, 2002, in Maniwa, Okayama, Japan. He was an active child who participated in baseball, swimming, and sumo tournaments throughout his school life. Mamehara started dancing at home when he was in elementary school after seeing his older sister's dance classes. A televised performance of Generations from Exile Tribe turned Mamehara into their big fan and motivated him to begin attending a dancing school in his second year of junior high. He specialized in the '90s hip hop dance and started teaching children at his dance school in his freshman year of high school. Mamehara grew up watching tokusatsu media, especially the Kamen Rider franchise, and aspired to star in it.
Mamehara graduated from high school in March 2021.

## Career
### 2019: Produce 101 Japan

After failing a series of auditions in 2019, Mamehara's older sister, a fan of South Korean Produce 101, suggested he try out for Produce 101 Japan. Having limited knowledge about K-pop, he initially refused to apply because he wanted to be a professional dancer instead. He eventually applied a day before the deadline, following his sister's encouragement. The show was held from September to December, where he finished first with 261,583 votes.

### 2020–present: Debut in JO1 and solo activities

Following an "intense" boot camp in South Korea, seventeen-year-old Mamehara debuted with the resulting boy group JO1 and its first single, Protostar, on March 4, 2020, through Lapone Entertainment. His win awarded him the choreographic center position in the group's debut song, "Infinity".
In November 2020, Mamehara was named Mezamashi TV's monthly entertainment presenter, making him the segment's youngest presenter at that time. He then took acting classes and made his acting debut in the Yoshimoto Kogyo-produced anthology film, Meters Away, Worlds Apart in 2021, alongside Produce 101 Japan's host and comedian Takashi Okamura. In 2022, Mamehara was cast as Kamen Rider Chimera in the film Kamen Rider Revice: Battle Familia [ja]. He reprised his role in Birth of Chimera (2022), an exclusive Toei Tokusatsu Fan Club spin-off film that delves into his character's backstory.
In 2023, he made his small screen debut in NHK's Super Human Fortress Record of Hiroshi War [ja], as the humanoid Hiroshi. In the following year, he made his TBS Sunday Theatre debut in the Ryunosuke Kamiki-led drama Diamond Sleeping in the Sea [ja]. In January 2025, Issei was cast in the lead role of Tsukasa Kiriki for the live action movie adaptation of the manga Bad Boys. In the following month, he was appointed as an ambassador to his hometown of Maniwa.

## Filmography
### Film

List of films, with the release year, role, and note :
| Year | Title | Role | Note |
| 2021 | Meters Away, Worlds Apart | Hiroki Asada | Segment: "Today is A Good Day" |
| 2022 | Kamen Rider Revice: Battle Familia [ja] | Nozomu Otani / Kamen Rider Chimera | |
| 2025 | Bad Boys | Tsukasa Kiriki | Lead role |

### Television

List of television programs, with the release year, role, and note :
| Year | Title | Role | Note |
| 2019 | Produce 101 Japan | Contestant | Finished 1st |
| 2020 | Mezamashi TV | Host of the month | |
| 2022 | Short Program | Hajime Toshino | Lead role; anthology series |
| 2022 | Kamen Rider Revice Movie Spin-Off Web Drama: Birth of Chimera | Nozomu Otani | Lead role; television film |
| 2023 | Super Human Fortress Record of Hiroshi War [ja] | Hiroshi Tanaka | |
| 2023 | Azatoi Type A to Z | Takuma | Drama segment of Azatoku Nani ga Waruino? [ja] |
| 2023 | An Encouragement of Laughing Life [ja] | Nobuyuki Yamamoto | |
| 2024 | Mame's and Sho's Best Holiday - JO1derful Tour | Himself | With Sho Yonashiro |
| 2024 | Diamond Sleeping in the Sea [ja] | Seiya | |