She will play alongside Lily Cole.

Sarah Bolger has joined Lily Cole and Scott Speedman on The Moth Diaries, which reunites Ed Pressman and his American Psycho director Mary Harron.
The Moth Diaries is based on the cult novel by Rachel Klein about an elite girl’s boarding school where a new arrival threatens established loyalties and may be linked to a spate of campus deaths.
Bolger will play Rebecca, a student who suspects the new student played by Cole is a vampire and has a crush on the literature instructor (Speedman) who leads a class on Gothic fiction.
Pressman will serve as executive producer and is lining up a summer shoot in Montreal with post-production scheduled for Dublin in autumn.
Dublin-based Bolger currently stars opposite Jonathan Rhys Meyers in Showtime’s series The Tudors and her feature credits include In America and The Spiderwick Chronicles.
Bolger is represented by CAA, who brokered the deal with Pressman Film Corp’s Jon Katz, and by Hamilton Hodell in the UK.
The Moth Diaries is an Irish co-production with David Collins of Samson Films.