The two stars, who have formed a folk duo, performed their first live show at an intimate gig held at the Omeara London, which was attended by the likes of Dermot O'Leary.
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Dressed casually in black jeans and a coordinating sleeveless top and white jacket, the actress sang a series of songs whilst playing the guitar.
Michael, who plays footman Andrew Parker in the Downton franchise, opted for dark trousers and a blue shirt worn over a white T-shirt.
The stars first met on the set of the period drama Downton Abbey, and soon discovered their shared passion for music. They quickly started to play music together in between shooting scenes.
Michelle singing at Omeara London
Connecting immediately, both on voice and guitar, Micheal and Michelle started playing regularly as a duo. Now, six years later, they made it official with their first record deal and debut EP, The Watching Silence.
The busy pair will be juggling their music around their acting commitments. Michelle recently said: "There was something about that time after the series [Downton] had ended... About looking at something with fresh eyes and feeling nervous about what's ahead. Then suddenly we were just writing music.
The actress and her co-star Michael have formed a folk duo
"It's a whole different set of skills and vulnerability. Acting tends to start with what's already written on the page. Music can begin anywhere. It's different and very freeing."
Michael added: "I will always love acting but there is something about us, some part of our characters that we haven't fully realised - and that's happening now." They both recently returned to screen for the latest Downton Abbey movie, A New Era.
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