When I was in high school, I got together with friends every week to play bridge. It was an excuse to sit around, eat frozen pizza, and spend a fun evening together. None of us were great players, but we all knew the basics and some of the subtleties — none of which I can recall four decades later — but when I saw this story by John Walters about a cheating scandal that has rocked the world of professional contract bridge, it all came flooding back to me.

The cheating was uncovered in much the same way the Absolute Poker/Ultimate Bet online poker cheating scandal was broken in 2007 — by players who spotted anomalies in what some players did, making big moves at the right time for the wrong reasons because, as it turned out, they knew which cards their opponents held. Those players then investigated multiple occasions that formed a pattern of odd play taking place, until they had enough evidence to take down the cheaters.

Walters lays out a similar scenario in his bridge story:

When Brogeland had been teammates with Fisher and Schwartz back in 2014, he had once quizzed them about a dubious move that proved advantageous during a match. “Why did you lead a club?” he had asked Schwartz, who replied, “I have to lead my partner’s suit.”

There was no way, at that point in the hand, for Schwartz to have known what Fisher’s long suit would have been. So how did he know he had to go with clubs?

Brogeland returned home to Flekkefjord, where he and his wife, Tonje, undertook the tedious yet engrossing task of watching Fisher and Schwartz win the previous year’s European championships via YouTube. (The ACBL, which oversaw the Spingold tournament, does not post its videos online.) “My average hours of sleep for an entire week was three hours,” he says. “My adrenaline was so pumped up.”

Thanks to a system called VuGraphs, bridge fans and watchdogs are able to see a chart of the complete hands all four players are holding during any one hand (after the match has been played). If an experienced student of the game matches those charts to the videos of the hands, he or she might eventually find a recurring signal being passed between partners, one that correlates to a specific play. “Bridge is a relentlessly logical game,” says Willenken, one of a coterie of top-level players whom Brogeland enlisted to help him uncover Fisher’s and Schwartz’s chicanery. “There’s a three-step process to cracking the code: Look at actions that are illogical; find a disproportionate amount of winning hands preceded by illogical actions; and analyze what is going on in those hands.”

Read John Walters’ full piece here.