Jeff Probst

For its 29th season (Wednesday, 8/7c, CBS), Survivor is reviving its Blood vs. Water theme — in which loved ones compete against each other. This time, however, all the players are new to Survivor, as opposed to in Season 27, when "Blood vs. Water" made its debut.

"Blood vs. water had such a positive response from the audience that we fell in love with the idea and decided, let's just do it again and let's twist it and not bring any returning players back, and see what that does to the dynamic," host Jeff Probst tells TVGuide.com. "And it definitely shifted it. People came in out of the gate saying, let's let loved ones dominate this game and try to get as deep as we can with as many pairs. So right from the beginning there was a new strategy."

Photos: Meet the cast of Survivor: San Juan del Sur

The show is also bringing back its "Exile Island" twist for Survivor: San Juan del Sur. At the beginning of each episode, a pair of loved ones will go up against each other in a "hero challenge." The loser of the challenge is sent to Exile Island.

"We were looking for a way [to have] conflict straight out of the gate," Probst notes. "Do I not try? Because if I don't try and I let my loved one beat me, what have I just told this tribe of people? They're going to vote me out. So instead you have to say, 'Uh, sorry, honey. I love you, but I'm about to kick your ass.' Until it's over and then your loved one is crying as they're being sent to Exile and you're going, 'Oh my God, what did I just do? I was happily married five minutes ago.' ... It's so easy to say, just do what you need to do before the game starts. And then when you get into the game and your loved one does what they need to do, I think it hurts a lot more than you anticipated."

Among the 18 castaways are former MLB player John Rocker, who's best known for statements he made to Sports Illustrated in 1999 disparaging "queers with AIDS" and "foreigners" in New York City; and Amazing Race twins Natalie and Nadiya Anderson. And, according to Probst, it's one of the most unpredictable seasons in Survivor history.

"This is a very unorthodox season," Probst says. "Some seasons just roll along and you can almost predict it. This season, I couldn't have predicted the way it was going to go. I would have never predicted who was going to win or be in at the end. And I hope that's the same journey that the audience has. Just so many weird things happen. Tribes have issues that they have to deal with me about, and they're losing things and wanting to trade for things and running out of things. It was just a constant, daily, 'What? What happened now?' I think there are a lot of things we haven't seen in a while, and I think the audience is going to enjoy it. I think it's going to feel refreshing and different."

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Check out Probst's take on the nine pairs below:

Dale and Kelley: This father/daughter relationship has definitely had its share of ups and downs in the past, Probst notes. But Kelley's main worry now is her dad's social skills — or lack thereof. "Dale lives on a farm and doesn't really talk to anybody, and that was his daughter's biggest concern," Probst says. "'My dad is a social outcast, and he's used to doing things his own way. I don't know how he's going to do in the game, and I don't want him to drag me down.' ... You have a father/daughter and the father loves the daughter, but the daughter looks at the dad as a liability."

Jeremy and Val: Look for this married couple (he's a firefighter, she's a police officer) to clash early on about their collective Survivor strategy. "Jeremy, it was clear from the beginning, was worried about his wife and wanted to take care of her, and Val couldn't say fast enough, 'Don't worry about me because I'm not going to be worried about you. I'm a cop. I do just fine,'" Probst recalls. "So, that was an interesting relationship. Also their approach to the game — Val considers herself to be a very good reader of people and manipulator of people because she's a cop, and Jeremy comes at it more from [wanting to form] a brotherhood."

Drew and Alec: These brothers from Florida are "the prototype for sibling rivalry," according to Probst. "Drew is the older, cocky [sibling], beating his brother up at every occasion. And Alec is looking for an opportunity to shine." Right out of the gate, Alec lets his desire to one-up his brother cloud his better judgment during a challenge. Will it be an irreversible mistake? At the same time, Probst says, "You can't help but kind of root against Drew a little bit, because he's so cocky you want to see the underdog have his day."

John and Julie: Rocker is probably the biggest wild card heading into Season 29. Will he be able to change people's minds about him? "That's the great question," Probst admits. "Survivor is not a show that you're doing on a soundstage with air conditioning and craft services.Survivor's shot in a jungle with nothing. So your true personality always emerges, and that's what I think is going to be interesting about watching Rocker. ... He's coming in with a knapsack of disadvantage, because people are going to judge him. If he turns it around and is actually a different person and can win people over, it would be a great hero story. If he's the same guy and immediately starts to bully and push people around, then people will probably vote him out." As for Rocker's girlfriend of four years, Probst says: "Julie is concerned that John is going to be a liability for her. She told us before the show, 'I've dealt with this for the entire time of our relationship, for four years. I walk into rooms where people have already judged John and they're therefore judging me, and that's not good.' ... But that's one of the interesting things about Blood vs. Water. Your loved one can help you or hurt you, and sometimes there isn't anything you can do to stop it."

Josh and Reed: A gay Christian couple from New York (Rocker will love them!), both Josh and Reed are Survivor superfans. "They're very active in their church, but they live a lifestyle that some people in their church don't support," Probst says. "I was really impressed and proud that they wanted to come on our show, endure this adventure, and be honest about who they are in the hopes that it'll help wake people up. ... They know what they're doing in the game and I think people are going to enjoy them and — at least out of the gate — root for them."

Jon and Jaclyn: The season's eye candy couple, Jon is a Michigan State football player and Jaclyn was named Miss Michigan in 2013. But their time on Survivor won't exactly be a fairytale, Probst cautions. "They're young and loving," Probst describes. "But what's interesting is watching their relationship play out. They're a couple and they love each other, but this game is hard. And, give people enough time together on Survivor, they will argue, no matter how much you love each other. There's an honesty to watching their relationship that I don't recall us ever doing before."

Missy and Baylor: Missy's 20-year-old daughter Baylor has "done a lot of self-parenting," Probst says. "There's a real clear connection between the two, but it doesn't necessarily appear that it's mother/daughter." But they're definitely a duo to watch. "I think the hardest [pairing] in Blood vs. Water is for the parent that's playing with a child," Probst says. "And when you're a mom I think it's the hardest of all. I think being a mom with your daughter would be the most difficult position to be in because you birthed her. There is no tighter connection in the world. ... If the only way you can move forward is by getting rid of your child, can you do it? Or do you just fall down on the sword and say, I just can't do it?"

Keith and Wes: "Keith is one of my favorite new players," Probst says of this father/son team of firefighters from Louisiana. "He didn't know the game at all ... so watching him learn how to play Survivor is fantastic, because he has a way of speaking that you just don't often see on television."

Natalie and Nadiya: Probst says he was unfamiliar with the Amazing Race "Twinnies" going into the season. "Now that it's over, I'm glad I didn't have any preconceived ideas," he says in retrospect. "I didn't know they were controversial. ... I just thought they were kind of lippy twins who were very colorful and had funny things to say." Not that the sisters tried to hide their prior reality competition experience. "They said in the very first episode, 'What we learned fromAmazing Race is not to judge a book by its cover, because you're going to be wrong a lot. So we're not judging anybody here yet. We're going to wait and see what happens," Probst says. "And then the season starts and oh my God, the game was on."

Which team are you excited to see on Survivor: San Juan del Sur? Meet the cast in the video below:

Survivor airs Wednesdays at 8/7c on CBS.

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