Portia de Rossi has been cast in a "top secret" role in the fourth season of Scandal.

The actress's wife, Ellen DeGeneres, revealed the news on Twitter, writing: "So annoying when people brag on twitter & that's why I'm not tweeting that Portia just signed on to do a top secret arc on "Scandal". Oops."

It is not yet known what role de Rossi will have in the upcoming season, but it has been confirmed that she will appear in multiple episodes.

Scandal returns to ABC in the US on September 25.