By now, you'll probably be aware that Niall Horan and Lewis Capaldi have struck up a bromance for the ages.
The Irish boybander and the Scottish singer recently did a joint interview that showed how they are kindred spirits.
Capaldi is even joining Horan as the support act on his US tour in 2020.
Now, they've taken their friendship a step further and have collaborated on a cover together.
It's not a Christmas song, more's the pity - but their acoustic take on Katy Perry's 'Teenage Dream' is certainly different.
Capaldi even sneaks in a little peck on the cheek at the end. Can someone get these two in a studio together, please?
Watch fan-captured footage of their duet below: