According to E! Online, the 32-year-old "Twilight" star has been given a series regular role, although the exact nature of her character is being kept under wraps.
She joins alongside fellow newcomers Robbie Kay and Zachary Levi, as well as Jack Coleman who reprises his role as Noah Bennet in the series.
Milo Ventimiglia, Zachary Quinto and Ali Larter are among the original stars who have ruled out their return.
The show has been given a 13-episode order by NBC and will premiere later this year.