Filmed in Montreal, lip reading reveals that the actors sometimes speak in French to their targets, and sometimes in English. It is unclear how they decide which language to use, being that Montreal is French-dominant. Because of this, there is no dialogue in the final prints.
This show was on YouTube for well over a decade, before it ever made it to the American airwaves. In USA, it first aired in obscure TV channels, in the middle of the afternoon, then very late on Channel 13 in Los Angeles, at 11PM. On American television, it never gained the popularity it has known on YouTube.
Some people are surprised that none of the prank victims ever seem to recognize Denis Levasseur, the main prankster, despite that he has been pranking people for decades. The truth is that Denis is often recognized. In the 2024 biography: Denis Levasseur: A Hidden Camera Legend by Jessica Woonan, Denis says that around 5 out of every 10 people do actually recognize him, joking "...but the other five, I get them!"
Typically, the filming schedule of Just For Laughs Gags begins in early May and ends in early October. They film around 350 gags during this time. For each gag they prank between ten to twenty people and then edit it down to around the five best reactions.
The show's decline in popularity was two-fold: part of it happened when its uncontested star, Dany Many, left the show, then interest waned; the other reason was when the production started using very disturbing and unfunny gore elements as gags (such as cut fingers graphically shown being sliced and/or bloody.)