Call the Midwife is a British period drama television series based on the best-selling memoirs of former nurse Jennifer Worth, who died shortly before the first episode was broadcast. It is set in the 1950s, 1960s and 1970s and for the first three series centred primarily on Jenny Lee, based on the real Worth. In the first episode, set in 1957, she begins a new job as a midwife at a nursing convent in the deprived Poplar district of east London. The programme's ensemble cast has also included Jenny Agutter, Pam Ferris, Judy Parfitt, Laura Main, Miranda Hart, Helen George, Bryony Hannah, Charlotte Ritchie, Linda Bassett and Emerald Fennell. Vanessa Redgrave delivers framing voiceovers in the role of "mature Jenny", and continues to do so even after the younger version of the character was written out of the series.