The former Doctor Who star supported his beautiful other half at a screening of her new Disney film in Italy on Wednesday (18 February).
Now, that is a look of love if we've ever seen one!
This is the first time Matt and Lily - who also stars in Downton Abbey - have walked a red carpet together as they prefer to keep their relationship away from the cameras.
In December, gorgeous Lily explained to InStyle magazine: "in regards to your love life, you're just entering into a whole of pain if you talk about it. If you've never said anything, there are no sound bites to haunt you when you're crying into a box of Kleenex after it all goes wrong."
Lily stars as Cinderella in the new Disney live-action romantic fantasy directed by Sir Kenneth Branagh.
Prince Charming is played by Game of Thrones' Robb Stark – aka the very handsome Richard Madden. The all-star cast also includes Cate Blanchett as the wicked stepmother and Helena Bonham Carter as the fairy godmother.
It's released in March.
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