"The Amazing Race" ends in a cliffhanger

Natalie, left, and Nadiya must find the right key to unlock their next clue on "The Amazing Race."

Sunday's episode of "The Amazing Race" ended with a "To Be Continued...," leaving the fate of one team in the air.

The episode also concluded before the leg was officially over -- one team couldn't check in because of missing documents, while travel mishaps left two other teams still competing, a day behind everyone else.

At the beginning of the leg, the six remaining teams (Divorcees, Beekman Boys, Rockers, Twins, Texans, and Chippendales) were sent from Istanbul to Moscow.

There were no rules for which flights the teams could book. They ended up in pairs -- the Chippendales and rockers traveled to Moscow via Amsterdam and arrived first. The twins and Texans connected through Munich and were the next to arrive.

The Beekmans and Abbie and Ryan ran into major travel trouble -- their fight from Istanbul to Frankfurt was delayed, causing them to miss their connecting flight to Moscow, and the next flight wouldn't put them in Russia until the following afternoon. There was nothing they could do about it, other than sit and wait. While they waited, the two teams made a pact to run this leg of the race together.

While those two teams were stuck at an airport, the other four teams took on a Detour in Russia. They had to chose between "Synchronize" (performing a routine in a swimming pool with Russian synchronized swimmers -- all while wearing flowered bathing caps) or "Alphabetize" (head to the Russian State Library, choose four books from a list written in Cyrillic, look them up in the library's card catalog and find the books in the library's stacks).

James and Abba went to the library, but quickly realized finding the books would be too difficult and decided to go swimming instead. Trey and Lexi were also intimidated by the challenge's lack of English, but persisted and finished.

Over at the swimming complex, teams struggled to learn the choreography and earn the coach's approval. Natalie and Nadiya considered using their Express Pass to skip the challenge, but the Chippendales convinced them not to, correctly arguing that other teams were behind them and there was little chance they'd be eliminated this leg.

The next challenge was Roadblock. Teams had to find the Trees of Love, where one team member had to unlock 10 locks to retrieve an "Amazing Race" ribbon containing their next clue.

Trey and Lexi finished the task first and moved on to the Bolshoi, where host Phil Keoghan was waiting at the Pit Stop. The Chippendales were the second team to finish the leg, and the twins were third.

James and Abba, however, ran into a major problem at the Roadblock. The taxi that had their bags -- and, more importantly, passports -- was nowhere to be found. They moved on to the Pit Stop anyway for what would have been a fourth-place finish but Keoghan informed them that without those documents, they couldn't check in. The episode ended with them contemplating how they could find the taxi and their things.

Meanwhile, Josh and Brent and Abbie and Ryan finally made it to Moscow. They wanted to do the books challenge but realized the library was closed for the day, so the two teams had no choice but to swim. The divorcees seemed to master the routine easily, but Brent, it turns out, can barely swim.

We won't know how they'll fare -- or if the rockers will be able to continue the race -- until next week.

Tell us: Who do you think will win this season of "The Amazing Race"?