After graduating from Columbia University, with a degree in cultural anthropology, Jamil decided on a career in television as a means of educating people about diversity. Since then she has had small parts in movies such as 25th Hour, Highway, as well as in the 2004 television series Espionage.
She is perhaps better known for her regular appearances as the host of the NYCTV programs Cool In Your Code and Paradetown USA.
As a model with Ford Model Management she has also appeared in a number of television commercials and fashion ad campaigns. In 2002, she was featured in an advertisement campaign by the investor Harrisdirect as a character named "Elsie Lee", who sparked a small buzz over the Internet at that time.
Mullen spent several days in a motion capture studio recording running, jumping, and combat animations, which were used as the starting point for Alyx's animation library.