At the 2016 Olympics in Rio de Janeiro, Katie Ledecky established herself as the new face of USA Swimming at 18 years old.
Now she's back following a successful college career at Stanford and is poised to dominate another Olympic games this summer in Tokyo, Japan.
In preparation for the games, here are five things you'll want to know about the Washington, D.C. native before she starts lapping her competitors in the pool.
The youngest US Olympian at the 2012 games
While she dominated in 2016, Ledecky first broke out in 2012 at the London Games. She qualified as a 15-year-old and was the youngest American participant in London that year.
As if making it to the Olympics at 15 wasn't impressive enough, Ledecky shocked the world when she won the 800m freestyle by more than four seconds and broke Janet Evans' American record set in 1989.
The performance earned herself the 2012 Best Female Performance of the Year and Breakout Performance of the Year at the Golden Goggle Awards.
Ledecky was born in Washington, D.C. in March of 1997 and attended school in Bethesda, MD. She graduated from Stone Ridge School of the Sacred Heart in 2015 and twice set the American and US Open record in the 500-yard freestyle and set the national high school record in the 200-yard freestyle twice as well.
Oh, and she grew up a huge Capitals fan.
Ledecky has a "slam" named after her
From 2014 to 2015, Ledecky established herself as the best women's swimmer in the world. In back-to-back years, she swept the 200, 400, 800 and 1500m freestyle at the Pan Pacific Championships in 2014 and the 2015 World Championships.
Sweeping all four events is now called the "Ledecky Slam." Ledecky wasn't able to complete her slam in the 2016 games, but that's only because the 1500m freestyle wasn't on the docket.
The Tokyo games have added the event, so Ledecky can officially go for her patented slam on the biggest stage.
When the 2016 Olympics rolled around, Ledecky was poised to take home multiple gold medals.
She swept every individual competition she was in, claiming gold in the 200, 400 and 800m freestyle. She also set world records in the 400 and 800m.
In the team events, Ledecky came away with a gold medal in the 4x200m freestyle relay and a silver in the 4x100m freestyle relay despite setting a new American record.
Events Ledecky will compete in this summer
As we've stated before, the 1500m meter freestyle is a new addition at this year's Olympic games, and Ledecky plans to swim in it. She'll also compete in the three other freestyle events included in the Ledecky Slam.
She will also compete in the freestyle relays for the U.S.
Women's swimming events will begin on July 25 in Tokyo and will run through August 5.