Although Niall may be an A-list celeb in his own right, it seems even he can get starstruck at times and that was evident on Saturday (7 December), as he eagerly took snaps of the famous Anchorman gang and claimed he'd had an unforgettable night.
Posing beside Paul - who plays Brian Fantana in the hit film - Niall gave a cheeky smirk to the camera and wrote: "What a super great guy ! Pleasure to work with!honour to meet! will never forget tonight!"
He also grabbed a picture with David Koechner and pulled a comical face alongside main character, Will Ferrell (aka Ron Burgundy).
Niall captioned his third and final photo: "Here he is! The one and only ! Will Ferrell !"
We're definitely sensing some super fan enthusiasm there.
But the the Irish singer's meeting with the Anchorman cast wasn't totally spontaneous, as he and the One Direction boys teamed up with the Hollywood actors to perform a skit for popular US show, Saturday Night Live.
After their appearance on the programme, Harry Styles echoed Niall's excitement by tweeting: "A massive thank you to @nbcsnl for having us back last night. It was a lot of fun. And now I fancy Paul Rudd."
So we're guessing that the One Direction guys have already bought their cinema tickets for the release of Anchorman 2: The Legend Continues later this month?!
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