She has appeared in a number of television shows and feature films. She acted as Janice Herveaux in the third season of the HBO series True Blood. Dawn played a reporter and Damon Salvatore's girlfriend Andie Starr in the hit CW show The Vampire Diaries. Wrapping up the 4th season on Heroes as the tattooed temptress "Lydia", she has also completed parts on TBS's My Boys, NBC's Knight Rider, TNT's Trust Me, and SyFy's Stargate: Atlantis, and recurred on CBS's How I Met Your Mother. Dawn is a lead in the SyFy movie HYDRA, and she is the voice of Pepper Potts in the new Avengers animated series on Disney XD. She appeared in the October 2009 issue of Maxim. Olivieri appeared on HBO's Entourage on September 13, 2009, and hosted a contest on Scripped. She most recently voiced in the video game, inFamous 2 as Lucy Kuo. Dawn can currently be seen playing the role of Monica Talbot on the Showtime TV series House of Lies.