Fraser made the surprise appearance at The Prince Charles Theatre on Friday (20 January) night, where he gave a short speech ahead of the screening.
“I am proud to stand before you tonight,” Fraser tells the audience in footage shared by the cinema.
“This is a film that was made in Britain. You should know that! Even the second one, too. Be proud. Thank you for being here.”
“We had no idea what kind of movie we were making when we shot this,” he continues.
“We didn’t know if it was a drama or a comedy or an action or a horror picture or a romance… all the above. We had no idea... until it tested in front of British audiences. Thank you for that.”
Fraser concluded his introduction by urging the audience to watch his new movie, The Whale, for which he is highly predicted to receive an Oscar nomination on Tuesday (24 January).
Fraser recently joked that he’d be up for a Mummy reboot as he’s never been “this famous and unsalaried at the same time”.
The actor’s press tour for The Whale has been littered with viral moments as fans praise the somewhat-forgotten actor’s much-lauded comeback role.
He plays a 42-stone (267kg) English teacher desperately trying to reconnect with his teenage daughter before it is too late.