This week is the start of the World Athletics Championships in Hungary.

It's the biggest track and field competition of the year.

And we wanted to bring you an episode we first made during last year's championships,

when what seemed like it should be the simplest possible rule led to a full-blown scandal.

That is as tough a break as I have ever seen in this sport.

The controversy got to the heart of one of the most basic questions in sports.

When does a race actually start?

There's confident, and then there's Tinea Gaither.

When I was younger, I used to beat up on the boys in PE,

and ever since then, like, I've been addicted to what I do.

What she does is sprint for Team Bahamas at the highest level.

I love the adrenaline rush that I get every time I line up.

I love making my family and my country proud.

I wouldn't choose any other career for myself right now.

Last July, Tynea was gearing up for a huge race in Oregon. This was the World Championships, which is the biggest championship that we have as professional sprinters for the year.

Tainia had been training for months day after day to get ready for this championship.

And she'd reached the semifinals of the 100-meter dash. These moments are everything to us. It was a beautiful day, high 70s, clear blue sky. Got out on the track, everything was perfect. I was really zoned in to this race because I knew what I was capable of. I knew that I was ready to run the race of my life. China Gayther of the Bahamas.

She lined up in the second lane. Twice, a world championship finalist over 200. And Tanya was locked in. If you go back and watch the video, you can just see how, like, tense my face looks. I'm like, okay, yeah, like, this is going to be great. She made sure to do her pre-race ritual. My teammates like to laugh at me about that. I slap my legs, and I throw my arms up in the air and throw them back over my head, and just do like a little shimmy with my shoulders. And then I get into the blocks. She set up in the blocks, one leg in front, one leg behind, with both her hands on the ground in front of her. I heard the crowd go quiet. Of course, you can hear, you know, a few murmurs or whatever,

but that's normal. And, you know, when everybody gets set and still, only when everybody's still, they'll stay set, and you'll come up in your set position. And then I heard the gun go off,

and I took off, and then I heard the gun go off again, and then I stopped.

At this point, it was all confusion. That second gun was officials stopping the race, because someone had broken a rule.

Can't see from this angle.

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