BBC favourite Call The Midwife is returning for three new series.
Series seven, eight and nine of the BBC One drama, which is set in London's East End, will take the nuns and midwives right into the mid 1960s.
Three Christmas specials have also been commissioned.
A sixth series of the show has already been announced and is due to air early in 2017.
Created by Heidi Thomas, Call The Midwife made its debut in 2012 and was based on the best-selling memoirs of former nurse Jennifer Worth, who died shortly before the first episode was broadcast.
The period drama frequently attracts audiences of more than 10 million viewers and has been sold around the world.
Charlotte Moore, director of BBC content, said: "I'm privileged to have Britain's most popular drama series on BBC One and this new three-series commission underlines our commitment to the show and secures its future on screen until 2020."
Heidi said: "In the 1960s Britain was a country fizzing with change and challenge, and there is so much rich material - medical, social, and emotional - to be explored. We have now delivered well over one hundred babies on screen, and like those babies, the stories keep on coming."
Audiences will return briefly to Poplar in December for the Christmas special before the residents of Nonnatus House are transported to the Eastern Cape of South Africa after receiving an SOS call from a tiny mission hospital.
Hope Clinic is understaffed, underfunded, and with a poor water supply, and the team discover that it is faced with closure.
The festive special will air on Christmas Day on BBC One.