The perfect storm: A high-banked oval crowded with the largest field of the season. Inexperienced or impatient drivers racing at more than 220 mph. Absolutely no room for error.
What was supposed to be a season-ending showdown at Las Vegas Motor Speedway became instead a script for disaster Sunday - a fiery 15-car crash that killed popular two-time Indianapolis 500 winner Dan Wheldon and left the shaken auto racing community to deal with uncomfortable questions.
The drivers knew the Las Vegas race was going to present challenges even before the season began.
The sleek, open-wheel machines of IndyCar had not raced at the track since 2000, and the now-defunct Champ Car Series was last there in 2005. Some of the drivers had been there before, but many had not.
So there was some initial fretting when second-year IndyCar chairman Randy Bernard announced a $5 million payday to any moonlighting driver who could win the race.
Bernard had hoped to land a superstar or two from the fender-rubbing NASCAR circuit. Maybe even former Indianapolis 500 winner Juan Pablo Montoya.
But nobody bit, despite interest from NASCAR driver Kasey Kahne, X-Games star Travis Pastrana and former CART champion Alex Zanardi.
"Hopefully they'll pick someone competent enough to drive those things because it is an IndyCar," Penske driver Will Power said shortly after the prize was announced. "You can't rub panels. You rub wheels, and someone's going flying."
Kahne said Monday that team owner Rick Hendrick was against his participation, and Hendrick confirmed it. Kahne's lack of experience in an IndyCar made it virtually impossible for him to win.
That left only Wheldon, winner of 14 races on ovals in IndyCar, including the Indy 500 in May, to be eligible for the $5 million prize. Bernard made that ruling because Wheldon did not have a ride this season. Wheldon put together a deal with Sam Schmidt Motorsports to race two weeks ago at Kentucky and for the prize Sunday.
"He wanted to do it in the worst way," an emotional Bernard said Monday.
A lot of other drivers wanted to be in the race, too.
Interest in the final race, which Bernard had worked tirelessly to create, had risen enough that sponsors wanted to get involved. Because IndyCar is in the final year of racing its current car design, teams had expendable inventory.
It led to 34 entries in the field. That's one car more than the Indy 500, five more than the race two weeks ago at Kentucky, and eight more than IndyCar had in Japan last month.