Leo Barraclough International Features Editor “Fingernails,” starring Jesse Buckley, Riz Ahmed and Jeremy Allen White, is to close the Karlovy Vary Film Festival. The tender and idiosyncratic romantic drama, co-produced by Cate Blanchett, is the sophomore outing from director Christos Nikou, who made a splash with his debut “Apples.” The film centers on the Love Institute, a scientific organization that tests the mutual compatibility of people who have decided to embark on life’s journey together.