In what may well be the funniest thing you see all day, One Direction members Louis Tomlinson and Zayn Malik — with a little help from Nickelodeon and a really good actress — pranked fellow members Niall Horan, Liam Payne and Harry Styles hard on set.

The actress pretended to be very pregnant to see what kinds of reactions the band would give her for some pretty unusual requests. They sing to her unborn baby (so freakin’ cute), move furniture and generally behave like slightly panicked gentlemen when they believe she’s going into labor.

Zayn can hardly keep a straight face in the beginning (seriously, watch him — we bet he’s not the best at poker) and Louis runs off to call his mum, who’s a nurse — but they’re both in on the joke. Harry, who legitimately thinks the woman’s about to give birth, looks horrified but does what he can to help, while Liam and Niall look simultaneously baffled, irritated and terrified.

Watch the hilarious video below — including a scene where the actress brings the giggles via flatulence.

Watch One Direction Get Pranked