Sei began his acting training at a performing arts school in Boston. After graduating from New York University (Tisch School of the Arts) with a BFA degree in acting and also studying acting at the Stella Adler Studio, he worked in Off-Broadway productions for two years as an actor and director (notably Pan Asian Repertory Theater company). During that time, he became increasingly interested in directing and in different training methods for actors. In 1996, Sei decided to leave New York in search of diverse approaches to acting that existed in the world. This research took him on a cross-continental trip across Europe, during which he met and worked with theater professionals from Russia, Bulgaria, Norway, Italy, England and Japan (including Yoshi Oida from Peter Brook's company). Sei arrived in Paris in 1997 and followed an apprenticeship with Amy Werba from the Actors Studio at the Bilingual Acting Workshop before accepting his position as an acting instructor. He also created the Four Corners Theater Ensemble and co-produced and performed in Arthur Miller's The Creation of the World and Other Business. He currently teaches at Bilingual Acting Workshop (the methods of Lee Strasberg, Stella Adler and Uta Hagen). Sei also teaches at his own acting studio (KEYS Acting Studio) for professional French actors in Paris and coaches actors privately.
Sei's directing credits include (English):
They also include (French):