Some people call it a "work" some people don't believe it really, but either way you look at and whether you believe or not the Montreal Screwjob that took place the fall of 1997 changed the look of Pro-Wrestling forever. To that point WCW had been very much so dominating in ratings and even after that point they were still winning the ratings war, but on that night in Montreal something changed. In one moment the WWF had made the hottest heel & the hottest babyface/free agent in pro-wrestling the people that would fit in those roles were Vince McMahon becoming the hottest heel in wrestling and Bret Hart becoming the hottest babyface and hottest free agent. But everything changed in the aftermath of the Screwjob because the long time WWF superstar left the company that made him famous for the competition and Vince had to start over with someone else. It all worked out in the end because everyone knows at this point how the war ended, but right let's take a trip back in time to that fateful night in Montreal Canada: 

Shawn Michaels vs Bret Hart (Survivor Series 97)

Famous Vince McMahon interview "Bret Screwed Bret"

Jim Cornette Shares his Thoughts on Montreal Screwjob