‘Race to the Center of the Earth’: A Contestant Faces Her Fear of Swimming (VIDEO)

What better motivation to conquer your fears than $1 million? That may help one of Race to the Center of the Earth‘s competitors tackle one of her biggest nightmares in the April 5 episode.

As seen in TV Insider’s exclusive sneak peek, Marilina of Team Southeast Asia is terrified of the open water in Vietnam as they continue on their trek to reach the location where their path intersects with the other teams’ (South America, Russia, and North America).

'Race to the Center of the Earth' Is an Intense Adventure in a Sprint Across the Globe (VIDEO)See Also

'Race to the Center of the Earth' Is an Intense Adventure in a Sprint Across the Globe (VIDEO)

See the first look at a series from the producers of 'The Amazing Race.'

“I’m terrified of swimming. This is a moment where my doubts are coming in about me as a team member,” she admits. “I’ve taken swim lessons recently to try to brush up, but it’s a really long distance. I’m feeling scared out of my mind.”

For this challenge, she and her team — James and Jay, all three of whom have been working together at an experiential high school in Seattle, Washington, for more than three years — must complete an open-water swim over 300 meters (longer than the length of six Olympic swimming pools) while towing backpacks weighing 20 pounds.

Watch the clip above to hear more from Marilina about how she feels about the challenge, see the team in the water, and check their current pace.

As for the other teams in this episode, one ends up “in a bind” due to a snowstorm in Canada, the “fabric of [another] will be tested” in South America, and the fourth “endures the longest day of the course” in Russia.

Race to the Center of the Earth Team Southeast Asia

National Geographic

Race to the Center of the Earth follows four teams of adventures, starting from different corners of the earth, racing to a buoy holding the grand prize. The first to arrive wins it all.

Race to the Center of the Earth, Mondays, 10/9c, National Geographic