It may seem like you're hallucinating for the first minute or so of this video, but no - that really is American TV host Jimmy Fallon and rapper Post Malone singing The Dubliners' 'Seven Drunken Nights'.

Why are they singing it, you might ask? We're not quite sure. Their attempt at a "lock-in, Irish pub-style" in the Tonight Show studio is a little cringe - particularly the comedy Oirish accents - but they give Ronnie Drew and co.'s song a decent bash.

It happened on Fallon's show the other night and has been shared on social media quite a bit since then.

Despite his stage name, Post Malone has no Irish connections - although he does apparently have a genuine grá for Irish trad, as we saw when he belted out 'The Auld Triangle' backstage at one of his gigs.

He plays Dublin's RDS later this month, so you can put in requests now... 'On Raglan Road', perhaps? 'The Wild Rover'? Anything's possible.

Watch it below:

https://www.youtube.com/watch?v=9VAat5xLUdo&feature=youtu.be