Harry Potter’ Star Fiona Shaw to Join HBO’s ‘True Blood’

 Vampire fans, look out! Deadline exclusively reveals that Fiona Shaw is coming to HBO's True Blood next season.

The Tony Award-nominated actress, who is best known for her portrayal of Aunt Petunia Dursley in the Harry Potter films, will star as Marnie, a plain and shy palm reader is who is eventually spiritually possessed by a commanding witch. The Golden Globe-winning vampire drama is scheduled to return in summer 2011.

The Irish-born Shaw appeared as Fulvia in the ABC drama series Empire in 2005, also starring Emily Blunt, Jonathan Cake, and Heroes' Santiago Cabrera. She's currently playing opposite Alan Rickman and Lindsay Duncan in a limited run of Henrik Ibsen's famed play, John Gabriel Borkman, in Dublin.

Here's a clip of Shaw talking about her character Petunia Dursley ahead of the London premiere for 2007's Harry Potter and the Order of the Phoenix: