Arielle Kebbel has landed a key role on The Vampire Diaries.

The actress - who has appeared on such shows as Gilmore Girls, CSI: Miami and Shark - will appear on The CW hit's seventh episode.

She'll play a character named Lexi, who producer Julie Plec describe as Stefan's "oldest and best vampire friend."

Might she cause problems between Stefan and Elena? Tune in. Find out.

In other casting news, Jasmine Guy will play Bonnie's mysterious grandmother throughout season one.

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