There's a joke about the size of Fassbender's penis and not needing to worry about a bit of cold water here but we're not going to make it. Oh no, we're much too high brow for that...
Michael Fassbender was on Fallon last night talking about his latest film 'The Light Between Oceans', in which he and Alicia Vikander play husband and wife (ooh err), and take part in a friendly game of 'Pen in a Bottle' which he clearly has had to master in Vikander's company.
And seeing as he was up for that game, Fallon invited him to play a game of 'Frozen Blackjack' (which involves the losing hand in a game of 'Blackjack' getting a crotch full of ice water) as well.
Turns out Fassbender is a gambling man with a wicked sense of humour and who enjoys the discomfort of others just enough to prove that he's definitely Irish. His slow realisation that things are going too well for him is just the icing on the cake.