Seth and Olive on season 29 of "The Amazing Race"
Seth and Olive could be one of the teams eliminated on the April 13, 2017 episode of “The Amazing Race” if one of them lost their passport. Trae Patton/CBS

Despite all being strangers, most of the teams on season 29 of “The Amazing Race” have proven themselves to be surprisingly strong. However, strength won’t matter when one team potentially makes a horrific mistake that could cost them their chance at $1 million on the Thursday, April 13 episode.

In a preview clip for the episode, the teams head to Zanzibar for their next leg, and following some points of contention in Sao Paolo, Brazil, tensions will be high as the threat of a Blind Double U-Turn looms.

Specifically, the threat of the U-Turn will weigh heavily as Ashton and Vanck try to get revenge on Matt and Redmond, who burned them in Brazil by reneging on a deal to do a coin flip for a first position at a helipad. And in the clip for the episode, it appears they may have succeeded when it comes to enacting their revenge, as Redmond and Matt race them on a beach and appear to warn them that they have something to fear.

“We’re gonna get you guys,” Redmond says in the clip. “I hope you’re scared. You should be scared.”

The tension also continues to boil between teammates Shamir and Sara, who ran into obstacles in Brazil after Shamir reacted badly to wearing a harness for the Roadblock.

However, those tensions might mean nothing after one team possibly makes a massive mistake that will be detrimental—and cost them their shot in the race completely.

Read: Where To Follow The Season 29 “Amazing Race” Cast On Social Media

“I cannot check you in until you have your passport,” Phil says. “If you lose that passport, your race is over.”

Which team will potentially get themselves eliminated because of their major mistake? Watch “The Amazing Race” at 10 p.m. EDT on CBS to find out.