Knowing about Glau's early career makes the start of her acting work rather unsurprising. The first role she was cast in (besides a lot of commercial work she did beforehand) was as a prima ballerina in an episode of Angel, the spin-off series of Buffy The Vampire Slayer that saw the titular heroic bloodsucker moving to Los Angeles and becoming a private investigator. The episode Waiting In The Wings saw him treating his employees to a night at the ballet. A night which goes rather tits-up when the immortal Angel notices that the prima ballerina, played by Glau, had previously appeared in a performance he'd watched over a hundred years ago. It turned out the director was a wizard, jealous that the dancer loved another, and cursed her to only dance with him. Forever. Nice guys are the worst, huh. It was a rather small role that mainly made use of Glau's dancing experience, but it was basically what made her career. Joss Whedon technically created Angel but was mostly pretty hands-off, spending more time working on Buffy, but he saw and loved Glau's performance in Waiting In The Wings. Then somebody suggested he put her in this Firefly show he was working on...