Maggie Grace has signed on for a role in 'The Twilight Saga: Breaking Dawn'.
The 'Lost' actress will play Irina, a vampire from the Denali coven who comes to help the Cullen family - made up of Robert Pattinson's Edward and Peter Facinelli's Dr Carlisle Cullen among a host of others - when they come into trouble in the final two instalments of the film, Deadline.com reports.
However, her character causes trouble when she sees Edward and Bella's (Kristen Stewart) daughter and assumes she is immortal - eventually bringing the evil Volturi clan to the Cullen family.
The Bill Condon-directed double bill will begin shooting in November, with the first instalment released in late 2011.
Although best known for her role in 'Lost', 27-year-old Maggie has also starred in a number of other projects - most recently as April Havens in Tom Cruise and Cameron Diaz's action comedy 'Knight and Day'.
She will next be seen in television movie 'When Calls the Heart' before a role in George Tillman Jr. film 'Faster'.