MovieLine: There are some movies that have little or nothing to recommend them, except as a frame for a performance. My Week with Marilyn is that kind of movie. Based on writer and documentary filmmaker Colin Clark’s memoir of the time he spent with Marilyn Monroe while working as an assistant to Laurence Olivier on the set of The Prince and the Showgirl, My Week with Marilyn manages to be both slender and overworked, a picture that states over and over again, in the baldest terms, how emotionally fragile Monroe was. We know, we know already. My Week with Marilyn has a TV-biopic sheen, and you could dismiss it easily — except for the fact that Michelle Williams, as Marilyn, both anchors the movie and upends it. Miss it and you’ll miss one of the finest performances of this year.