The Father (out Apr 1) has been nominated at the Oscars for best picture and it tackles the subject of dementia through the eyes of the sufferer. You're never quite sure what's real and what's not. Actors change. Storylines change. Small details within the apartment change. With the wrong actors, this could have come across as a gimmicky exercise but the two leads, Anthony Hopkins and Olivia Colman, are extraordinary. Grade: A.