Eion is known for his performances in the Emmy and Golden Globe winning HBO miniseries Band of Brothers, character roles in "Fight Club" , "Almost Famous", "Center Stage" and leading man opposite Antonio Banderas in HBOs "And Starring Pancho Villa as Himself". Eion was nominated for a Golden Satellite award and hailed by critics for a "beautifully understated performance that brings a striking balance to the piece". The movie's legendary writer-producer Larry Gelbart of M.A.S.H. fame was quoted in Variety as saying " I see Eion as a reincarnation of Henry Fonda. He's physically attractive and exudes an effortless sincerity, he has the whole actors ball of wax".
In September 2003, Variety Magazine honored Bailey as one of the top ten emerging actors to watch. He has appeared in Showtime's original movie, "Sexual Life", where he was voted the prestigious 'breakthrough performance of the year award' by audience members of The Phoenix International Film Festival after only twenty minutes of screen time.
Eion joined the cast of ER for half a season, and was recognized by People Magazine as one of the Fifty Most Eligible Bachelors of 2005 and US magazine named Eion and his cast mate Maura Tierney as one of the sexiest couples on television. Eion has since starred opposite Ellen Pompeo in the television movie "Life of the Party", for which he was awarded his first Emmy for 'Outstanding Performance in a 'Youth or Family Special'.
No palco, Eion apareceu em inúmeras peças, principalmente como Alan Strang na obra-prima psicológica "Equus" no Pasadena Playhouse. Neste papel atrevido que exige uma quebra mental mental e uma nudez total prolongada, os críticos mais uma vez encontraram a performance de Eion como notável. Variety o chamou de "excelente como Strang" Hollywood Reporter "perito" e Drama Logue observou que "seu desempenho se move para um crescendo profundamente movente pelo final das jogadas".
Mais recentemente, a sua vez, como Steve Knight em Showtimes, "Ray Donovan" atraiu a atenção junto com um seguidor internacional seguindo seu papel recorrente de vários anos no "Once Upon A Time" da ABC. Em 2017, Eion está atirando "The Last Tycoon" para a Amazon e sua turnê em estreia no drama náutico "Extorsão" com o nomeado do Oscar, Barkhad Abdi e Danny Glover, será lançado pela Lionsgate em 16 de maio.
