A dearly departed Irish grandfather has given mourners gathered by his graveside one final dose of laughter, in a funeral prank now watched by millions.

Shay Bradley, a grandfather of eight from the south of Dublin, passed away after a three-year battle with illness.

But not before he had the chance to craft one final hilarious message for his beloved family.

After his coffin was lowered six feet under, and a cacophony of bagpipes stopped playing, well wishers appeared instantly startled by the sound of Bradley’s voice.

“Hello? Hello? Let me out, it’s f—–g dark in here!”, the recording starts.

“Is that that priest I can hear?”

Then, the sound of knocking, seemingly six feet below from beyond the grave.

Tears almost instantly turned to laughter, as the realisation dawned they were being played a fool by a veteran of the Irish Defence Force, who happened to possess a wicked sense of humour.

His daughter, Andrea Bradley, later explained the joke was pre-meditated weeks in advance of his October 8 death, as his dying wish.

“Always the pranksters, you got them good Poppabear and gave us all a laugh just when we needed it!! I will love you forever,” she wrote.

“What a man, to make us all laugh when we were incredibly sad. He was some man for one man.”

Bradley’s granddaughter Chloe Kiernan told Mashable his closest relatives were in on the joke, to be sure the younger ones would not be frightened.

The video, which has since gone viral on Facebook and Twitter, has racked up more than two million views.