Four teams across the world compete in the ultimate adventure race for $1 million. Teams of co-workers, rock-climbers, cops and teachers are spread out across the world and racing toward the same finish line. As the race begins, teams must work together to win. For one team, a steep challenge on day one will test their mettle.

As the Race to the Center of the Earth heats up, teams are pushed to the limits of both mind and body. In Canada, a snowstorm puts the team in a bind. In Vietnam, one adventurer will have to face her fears. In South America, the fabric of the team will be tested. And in Russia, the team endures the longest day of the course.

The race continues, and for each team it will take physical and mental strength to endure. In Russia, car troubles jeopardize the team's lead in the competition. In Canada, relationships are put to the test. In South America, the team must make a risky decision. And Team Southeast Asia will face their most exhausting challenge yet.