Synopsis:

Tatiana Maslany (The Nativity, Picture Day) plays Sarah Manning, an outsider and orphan whose life changes dramatically after witnessing the suicide of a woman who looks exactly like her. Sarah assumes her identity, her boyfriend and her bank account. But instead of this solving her problems, the street-smart chameleon is thrust headlong into a kaleidoscopic mystery. Sarah quickly finds herself caught in the middle of a deadly conspiracy and must race to find answers about who her doppelganger really is…

Orphan Black airs on BBC Three in September.