Defenders of all that is good want charismatic Jamaican to beat former doping cheat.
Sport loves a spat between supposed "good" and "evil" forces. This year's contest for the 100m crown at the Moscow world championships provides exactly that.
A month ago in Rome, Usain Bolt was beaten for just the fifth time over the 100m distance. Who beat him? None other than 2004 Olympic 100m gold medallist and doping cheat Justin Gatlin.
The result provides perfect scripting for a duel. The pair will presumably line up in the final on Monday morning, August 12 (NZT) to contest the title of fastest person on the planet. Gatlin (9.94s) beat Bolt by only 0.01s but IAAF track and field chiefs, television networks and sponsors must be in a febrile state.
What theatre to think arguably the greatest sprinter in history is under threat - and from yesterday's man Gatlin, who, at 31, is five years Bolt's senior. Potentially, add fellow Jamaican Yohan Blake and American Tyson Gay to this mix and an explosive finale awaits.
Bolt races the 200m in Paris this weekend, when one imagines he will look to show his "stumble" in the Rome 100m was just an early-season speed wobble.
The world and double Olympic champion came out to the Stadio Olimpico in athletics' version of the Popemobile and was driven around the adoring masses before performing his usual theatrics; he beamed to the cameras, pointed at the sky and even got a great start. Then his legs failed him 50m in. His open-mouthed shrug in the aftermath was a helpless gesture.
Gatlin by comparison pumped his once-drug-propelled legs and never gave up. The man doesn't lack for tenacity, despite a four-year ban from 2006 for testing positive to testosterone. He insists he never knowingly took a performance-enhancing substance. Murky rumours did the rounds about a massage therapist rubbing dodgy cream into his buttocks. There's always a theory...
Anyway, Gatlin appears to be going about his resurrection successfully. Forgiveness is in the air.
He regularly tweets "inspirational" quotes such as: "I didn't change, I grew up, there's a difference." He has even linked himself to social causes, like the fight for same-sex marriage.
In quite an anti-sprinter way, he's taken to praising Bolt as his key rival, saying after the Rome race: "It's an honour to be able to race against him and compete against him. He's an inspiration for the sport. He's inspired me to be a better runner and a better entertainer for the fans. I just want to be able to give him some competition when he's at top form."
It's hard to believe leopards change their spots but there's always hope.
The difference is, if Bolt ever goes down that path, we can shut the gate on sport as we know it. No one will believe anyone ever again - forget Ben Johnson and Lance Armstrong, this will be uglier.
That's why Bolt has to win in Moscow. Fans need to know someone continues to wave an honourable flag, where a combination of supreme athleticism, fortuitous genetics and hard toil, trump all unnatural forces.