Michelle has taken the helm as leading lady in the BBC One drama, following Lacey Turner's departure after two series', and it looks set to be a good 'un.
The former Coronation Street star is playing a new character - Corporal Georgie Lane - and she spent three months filming in South Africa earlier this year.
Announcing her news on Instagram, Michelle shared a picture of herself on set. Looking far removed from the usual red carpet glamour we are used to, Michelle is in character and wearing combat gear.
Captioning the picture, she told her followers: "It's OFFICIAL- 7th September, BBC1 #ourgirl #GeorgieLane."
We can't wait - and neither can fans. One gushed: "OMG very excited now!" Another added: "This is too exciting! I'm buzzing!"
Following her departure from Coronation Street last year, Michelle has been in hot demand. Along with Our Girl, the actress has also landed a part in a new ITV drama this summer.
Dying her dark tresses platinum blonde for the role, Michelle has been cast as Tina, the wife of footballer Bobby Moore, in the forthcoming series.
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