Rei Dan is a Japanese actress whose career began on the stage and expanded to include film, television, and occasional voice acting roles. Born on August 4, 1971, in Hyogo Prefecture, her birth name is Mayumi Yamazaki. She is primarily known as a highly accomplished stage and screen actress rather than a voice actor specializing in anime.

Dan's professional foundation was built at the renowned all-female Takarazuka Revue. She joined the company in 1992 and became a celebrated top star (known as a top娘役, or top female role player) for both the Moon and Star troupes. During her time with the revue, which lasted until her retirement from the company in 2005, she was known for her graceful stage presence and classical beauty. This background as a performer in elaborate musicals and dramas established her as a versatile and disciplined talent in the Japanese entertainment industry.

After leaving the Takarazuka Revue, Rei Dan transitioned successfully to screen acting, making her film debut in 2006 as the heroine in Yoji Yamada's film Love and Honor, opposite Takuya Kimura. This performance garnered critical acclaim and earned her several prestigious newcomer awards, including the Blue Ribbon Award, solidifying her status as a serious film actress. Her filmography is extensive and includes roles in major productions such as Kabei: Our Mother, for which she received a nomination for Best Supporting Actress at the Japan Academy Prize, as well as Ninja Kids!!!, Ace Attorney, and Silent Parade. She is also a familiar face on television, having appeared in numerous dramas and the prestigious taiga historical epics Taira no Kiyomori and Awaiting Kirin.

While her primary focus is on live-action performance, Rei Dan's career includes contributions to voice acting. Her first voice acting role was in an animated project in 2006. She provided the narration for the 2010 film Kyoto Story. Her most notable work in animation is in the 2011 feature film Tōfu Kozō, where she voiced the character Akane Murota, confirming the user's example. These roles, however, represent a small facet of her broader and highly celebrated acting career, which remains centered on stage and live-action film and television.