‘Survivor: All Stars’ end promises big surprise

Every round of “Survivor” has some small lesson on human behavior. Often they’re in the area of social interaction and run along the lines of: One bad apple spoils the bunch.

We’ve seen one lone, grumpy, socially inept castaway after another destroy dynamics for entire tribes. They made for great TV, but they made the players’ lives miserable (need we even say Jerri Manthey?).

For the current edition, “Survivor: All-Stars” — which crowns a winner Sunday night, then brings the 18 familiar faces back for a live show and more bickering — it’s a lesson about power.

Put simply: When someone tries to seize power, and the rest of the group goes along, that power becomes very real and very solid.

Certainly, that’s big stuff for a silly game, but Rob Mariano — Boston Rob, if you’ve been watching — has been the 600-pound gorilla for weeks because, as much as anything, the rest of the bunch on Panama’s Pearl Islands are calling him the big ape. (That didn’t come out right, but you know what I mean.)

He squares off in the finale against Amber Brkich, Rupert Boneham and Jenna Lewis, following the elimination of Tom Buchanan in Thursday night’s episode.

Host Jeff Probst, in a conference call, said he finds himself wanting to cheer for Rob.

“You have to give a lot of credit to Boston Rob,” he said. “It’s really tough to come in and take the leadership role.

“A lot of people are not pulling for Rob; they’re pulling for the underdog. I see him as the underdog,” Probst said. “Here’s this blue-collar guy from Boston, he comes in, tucks the girl under his arm, and says, ‘Stick with me.’ That is romantic… .”

He said Amber and Rob seem to have constructed a team where he takes the bullets and she flies under the radar, but Probst wouldn’t talk about who, if anyone, is playing whom.

“If Rob really has fallen in love with this girl,” Probst said, “that’s when guys start making fatal mistakes.”

He also said he hopes there are no more all-star versions.

” ‘All-Stars’ was a lot of fun,” he said, “but I would vote to never do it again. I think the game is better played by strangers.”

Still, Probst said, Sunday’s tribal council is “probably the most honest and emotional final tribal council that we’ve had since the first season, because they were friends and because there were a lot of hurt feelings.”

There were also some bruised egos early on, when the cocky all-stars tried to show off their now-honed survival skills, and could not make a fire.

“It was an impossible situation, and we knew that,” Probst said. “We had local guides who told us the conditions of the woods, the climate, makes it a situation where they wouldn’t get fire. But they didn’t know that.”

As for Sunday night, CBS promos have been promising a mammoth surprise, a bombshell guaranteed to shock the world. Or something close.

“I don’t write the promos,” Probst said. “But there is a pretty good reveal on the live show.”

And if there isn’t, add one more lesson to the “Survivor” list: Don’t trust TV promos. As if you didn’t already know that.