Dawn Olivieri (born on 8 February 1981) is an American actress who has appeared in a number of television shows and feature films. She is currently on Showtime series House of Lies as a competitive and libidinous management consultant. She also acted as Janice Herveaux in the third season of the HBO series True Blood. 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.