Call The Midwife is losing three key characters in unexpected twist

Don't panic, but when Call the Midwife returns at the end of the year, it's set to look very different - given the fact that three of the main actors have just announced they are leaving the show!

Come December, we won't be seeing any more of Patsy Mount, played by Emerald Fennell, Delia Busby, played by Kate Lamb, or Sister Mary Cynthia, played by Byrony Hannah. It's been reported that the three actors are keen to gain experience outside of the BBC drama, so it seems that the numbers in Nonnatus House are sadly about to drastically decline.

However, there is some good news. Reportedly, none of the three characters are set to be killed off - so there could be potential for them to return further down the line.

Bryony's character Sister Cynthia is one of the longest-standing members of the period drama, introduced in the very first season as the caring and intelligent midwife.

Patsy and Delia are newer additions to the cast, with Patsy having joined the gang in season 2, and Delia joining even later in the third season back in 2015.

The two characters became a couple during the course of the show, and delighted fans during the season six finale when they shared a kiss after having been parted for months, while Patsy cared for her sick father.

The news comes despite Emerald Fennell's assertions that the story "wasn't over" for the pair, so the revelation that her and Kate's will now depart the show is sure to come as a sad shock for many fans.

For Sister Mary Cynthia, however, season six finished on a sadder note. She had returned to Poplar after spending some time in a mental institution, as she came to terms with the sexual abuse she'd endured.

It seemed briefly that everything was looking up for her when she was able to return to Nonnatus House, but hopes quickly faded as her fellow nurses and nuns realised she still wasn't well. Sister Mary ended the series returning to care facility Northfield.

The three stars aren't the only members of the Call the Midwife cast to quit the show since it began in 2012. Popular characters from the first few series, including those played by Jessica Raine (Jenny Lee) and Miranda Hart (Chummy) have since left the BBC drama. But there are some long-standing members who remain, including Laura Main (Sister Bernadette), Helen George (Trixie), and Judy Parfitt (Sister Monica Joan).

Despite the mass exit, the drama is set to gain a character too, so all is not lost! In exciting news, the BBC programme has just hired its first black nurse, Lucille, who will be played by Leonie Elliott. She will join the cast in a storyline that nods to the period in the 1960s where large numbers of nurses from the Caribbean moved to the UK to work.

So lots of changes, but whoever's on board for Call the Midwife series seven, we can't wait to watch!