'Big Brother' introduced several surprising twists on Thursday's season 13 premiere. Three past couples returned, including infamous season eight winner Evel Dick and estranged daughter Danielle.

Season 12 couple Rachel and Brendon returned as well, revealing that they're now engaged, and Jordan, who won season 11, joined the show, along with boyfriend Jeff.

Later in the episode, Julie Chen revealed yet another twist called "The Golden Key," which grants immunity those who survive elimination. Anyone who possesses the key will automatically make it to the top 10.

[AOL TV]