Basically, Bret was going to leave the WWF in 1997. On November 9th, he was going to beat Shawn Michaels and then lose his final match by disqualification. Unfortunately, Vince McMahon decided to illegally call the match just as Shawn Michaels put Bret Hart in the famous sharpshooter move. Hart was most likely going to reverse this move and win the match, but McMahon decided to make Bret lose for whatever reason.
Bret was in shock and he spit on McMahon before leaving. He also expressed his anger by destroying a few TV cameras after the match.
During this era, Shawn Michaels was a member of a highly influential clique that often controlled the outcomes of various matches. Their power behind the scenes was linked to Vince McMahon and it led to the 'screwing over' of Bret "Hitman" Hart, a respectable, skilled wrestler.
To this day, Shawn Michaels is hated in Canada (Hart's homeland) and the crowds often boo him or shout "You screwed Bret!" as a constant reminder of this unfortunate, unfair event.
The Montreal screwjob refers exclusively to the night of 11/9/97, but many comparisons are made to this famous match. The recent firing of Matt Hardy brought up a deluge of references to the untimely release of an excellent wrestler, Bret Hart.