The Switch actress will play young army recruit Molly in a one-off 90-minute drama titled Our Girl, reports The Sun.
Molly joins the Royal Army Medical Corps after throwing up in the doorway of a recruitment office while out celebrating her 18th birthday. Our Girl follows her through training and into active service in Afghanistan.
Former EastEnders star Turner described Molly as "an interesting character who shows such strength and determination".
A BBC spokesperson added: "Molly is as colourful, unique and powerful as Stacey Slater was when she first arrived on the channel eight years ago."
