The new season will revolve around an unexplained virus.
Casualty has confirmed the return date for its new 12-part storyline which will see an unexplained virus rip through the ED.
Season 41 of the medical drama - which is titled Lethal Legacy - will premiere on Saturday 25 April at 8:45pm on BBC One. Episodes will also be available at 6am on BBC iPlayer on the day of transmission.
When a surge in patients with an unexplained virus causes the ED to buckle under the strain in the new season, the army is deployed to keep the peace and Flynn (Olly Rix) is forced to face a long-buried secret.
Meanwhile, Stevie (Elinor Lawless) and Matty (Aron Julius) - still reeling from their loss - turn to an unexpected source of comfort, a decision that pushes Dylan (William Beck) away from his son.
Elsewhere, Jodie (Anna Chell) goes to great lengths to explore a disturbing truth buried deep within a local estate.
"With old wounds reopening and trust wearing thin, the team must pull together or watch everything unravel," the BBC has teased.
"Facing off against the team this series is the domineering Colonel Jack Bard (Mark Womack), whose powerful hold over his subordinates, and ties to Flynn, threaten to shake the bedrock of the ED when history begins to repeat itself".
Casualty aired its season 40 finale, Learning Curve, on Saturday.
The episode featured a tragic death, and set up some big storylines for many of the surviving characters heading into the next season.
Read more:
Casualty boxset finale airs devastating death of Holby City doctor in early BBC iPlayer release
BBC confirms schedule shake-up as Casualty set to take break
Previous episodes of Casualty are available to stream on BBC iPlayer now.
Casualty returns on Saturday 25 April at 8:45pm on BBC One and 6am on iPlayer.
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Molly Moss is a Trends Writer for Radio Times, covering the latest trends across TV, film and more. She has an MA in Newspaper Journalism and has previously written for publications including The Guardian, The Times and The Sun Online.
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