The Master of the Wheel Gonzalo Garcia Pelayo

1Pelayo's Early Days of Wheel Bias Analysis

Gonzalo Garcia Pelayo was born in Madrid on June 25, 1947. He enrolled in Spain’s Official Film School in the 1960s, but his filmmaking education came to an abrupt halt when the institution unexpectedly closed.

At that point, Pelayo turned to music, accepting a job at National Radio, which laid the foundation for his successful career in the entertainment industry. Among his most notable achievements are the creation of the Andalusian rock genre and his production work with renowned Spanish artists such as Carlos Puebla, Luis Pastor, and Maria Jimenez.

During the 1970s and 1980s, Pelayo revisited his passion for filmmaking and directed several feature films, including Living in Seville and Manuela. His journey as a roulette player began in the early 1990s when he decided to pick up the game as a hobby.

Initially, he played purely for fun at Casino Gran Madrid, but he soon noticed that certain numbers seemed to appear more often than others. This realization prompted him to begin recording the outcomes of spins to see whether his suspicions were justified.

Pelayo quickly realized that it was too laborious for one person to gather data on multiple wheels, so he recruited his son Ivan and daughter Vanessa to help him. They spent countless hours each day at Casino Gran Madrid documenting the results produced by the roulette wheels.

While his children focused on data collection (they manually recorded more than 30,000 results!), Pelayo, who had a knack for mathematics, set out to develop computer software that would allow him to analyze the recorded data accurately.

The program he wrote in the simple QBasic language assigned a numerical value to every pocket on the wheel: the more frequently a number appeared, the higher the value it received.

This enabled Pelayo to create a profile for each wheel his children tracked, helping him identify biased wheels and compile lists of numbers with abnormally high hit frequencies. He reasoned that these numbers were more likely to occur. It was a turning point for the entire Pelayo family.

2The Pelayos' Success in Casino Gran Madrid

After profiling numerous wheels, Pelayo determined that exploiting these biases could negate the casino’s edge and give the player an impressive 6% advantage. Of course, the player would not win every spin, but someone armed with this information could avoid losing to the house over the long run.

The roulette team expanded as more members of the Pelayo family joined. Pelayo understood that losing streaks were inevitable despite their edge and that he needed a larger bankroll to withstand those dry spells.

Although he was a successful filmmaker and music producer, he was by no means wealthy. Pelayo therefore sold the rights to one of his documentary films, which helped him boost the bankroll to about $2,200.

Because Pelayo’s simulations revealed pocket bias, he and his relatives decided to bet straight up on the favored numbers. Individual numbers had lower odds of appearing (1 in 36), but they offered higher payouts of 35 to 1. The Pelayos’ modest starting bankroll also helped them avoid detection during the early stages of their roulette run.

The family had a rough start, losing half of their initial $2,200 while playing at Casino Gran Madrid. Despite the setback, the Pelayos persisted and continued wagering on the favored numbers.

The bias soon paid off, prompting the family to visit the casino as many as six times a week. With the entire family now involved, the Pelayos could assign one member to each biased table. This tactic proved effective because it prevented the Casino Gran Madrid staff from realizing they were all connected.

After a few months of play, the family grew their modest $2,200 bankroll to more than $100,000. Encouraged, they began placing larger and larger bets on the biased numbers. Despite this success, the Pelayos still experienced cold streaks, at one point losing a sizable $80,000.

3Casino Madrid Strikes Back

These cold streaks were more than offset by the Pelayos’ massive wins, which totaled hundreds of thousands of dollars. Pelayo forbade team members from tipping the dealers. This policy, combined with the astonishing profits they generated, soon attracted the attention of Casino Gran Madrid.

The floor personnel were ordered to monitor the Pelayos’ play to determine what was happening. They tried various tactics, from pressuring team members and instructing croupiers to spin the ball faster to swapping wheels between tables.

All these efforts proved futile. After months of playing the same biased wheels, the Pelayo team could identify them by tiny physical imperfections, such as scratches.

The casino responded with accusations of cheating and attempted to ban them permanently. The situation escalated to the point where the matter was taken to court.

The Spanish Supreme Court ruled in the Pelayos’ favor, reasoning that exploiting biased wheels is a legitimate form of advantage play, not cheating. The family eventually left Casino Gran Madrid – not because they were barred but because the casino replaced the wheels, eliminating the bias. By the end of this stint, the biased wheels had made the Pelayos $1 million richer.

4The Pelayos Take on Las Vegas

Their tremendous success at Casino Gran Madrid inspired the Pelayos to tour casinos throughout Europe, with Amsterdam as their first stop. Their winning streak continued there, and over several months they amassed approximately $400,000 in profits.

These results aroused the Dutch casino’s suspicions, so management contacted Casino Gran Madrid and the Pelayos were exposed. As the family traveled to other major European cities such as Vienna and Paris, casino after casino barred them for their advantage play.

They typically exploited the tables in each country for three to four months until local casinos detected them and asked them to leave. As their reputation spread across the continent, a security guard at a Copenhagen casino even threatened them with a gun when they tried to enter the premises.

Pelayo’s nephews decided to quit, and the team shrank to three members: Pelayo, his wife, and his son, Ivan.

With European opportunities drying up, the Pelayos explored the prospect of taking on roulette tables across the Atlantic. Las Vegas looked like the perfect destination for advantage players of their caliber.

However, an assault on Sin City posed several challenges. First, the roulette tables there operated under American rules and used wheels with both a single and a double zero, which doubled the casino’s edge to 5.26%.

Enhanced surveillance was another hurdle; it was far more difficult for advantage players to slip under the radar in Las Vegas casinos.

The family maintained their edge on double-zero wheels by seeking out more pronounced number biases. To avoid detection, team members tried to blend in as much as possible by altering their accents.

5The End of Pelayo's Roulette Career

The Las Vegas campaign proceeded smoothly for a while, until Pelayo hit a major snag one night. He was wagering huge sums on two biased numbers when something extraordinary occurred. The number with the lowest probability according to his computer simulation – 19 red – miraculously appeared.

Ironically, 19 red sat right between his supposed sure winners, 8 and 31 black. Pelayo again covered the two likely numbers with sizable bets, reasoning that the odds of 19 red appearing twice in a row were virtually nonexistent. To his shock, the ball settled on 19 red again on the very next spin!

The advantage player still did not give up, convincing himself there was absolutely no chance the number would hit three times in a row. Unfortunately, that is precisely what happened when the wheel produced the dreaded number yet again.

Overcome with a sense of utter failure, Pelayo collapsed on the casino floor from fatigue and disappointment. He was in such poor condition when taken to the hospital that staff initially thought he had suffered a heart attack.

After he recovered, he returned to the casino a couple of days later, only to realize he had completely lost his confidence as an advantage player.

As Pelayo explained in an interview with U.S. National Public Radio, it was similar to what happens to a bullfighter who has been gored and is afraid to face the bull again. The family ultimately decided to quit permanently and return to their normal lives in Spain.

Pelayo ended his roulette career with more than $1.5 million in net profits. His remarkable story has inspired aspiring roulette players worldwide, so much so that he published it in his 2003 book The Fabulous Story of Los Pelayos (La Fabulosa Historia De Los Pelayos), later adapted for the silver screen.

Today, Pelayo continues to collect data and study probabilities, but he has shifted his focus to other forms of gambling, most recently poker.