Below are the five wildest moments, which were not for the faint of heart. Camel milk, elephant feces, and maggot-infested water buffalo all made appearances, so in the event you're easy to make queasy, you've been warned!
Drinking Milk From A Camel
On their two-day journey, the duo encountered a one-humped camel -- also known as a dromedary -- which Grylls suggested that they milk to stay hydrated. But milking a wild animal proved to be easier said than done after Grylls warned his movie star companion that the it might be aggressive.
Grylls went first and managed to get milk in the canteen, but when Gordon-Levitt went for it, the camel kicked him right in the shin. Ouch!
Luckily, Grylls squeezed out enough of the salty treat to share. Yum?
Gordon-Levitt conquered his fear of heights by rappelling down an 80-foot rock formation using only a small rope and harness. But it wasn't easy. Although Grylls reassured him that everything was going to be alright, the actor wasn't buying it. "No, sorry man, I'm from a different tradition than that," he said. "I want to know that it's safe, and I've never done this before."
"My biggest fear is my fear of heights," Gordon-Levitt said while Grylls was trying to coax the nervous actor over the edge. "My instincts are saying, 'Don't do this. Don't go over the edge.'"
Eventually, the actor did go over the edge, and apparently loved every second of the stunt. "That was f-cking awesome, dude!" Gordon-Levitt exclaimed. "Dude, that's fantastic. I want to do that again."
Water Buffalo -- It's What's for Dinner!
While trudging through the canyon, the men encountered a large alligator guarding a water buffalo carcass in a small creek. Apparently it smelled as disgusting as it looked.
"I think I can safely say that is the worst smell I've ever experienced in my life," Gordon-Levitt said. "It looked like black garbage bags full of blood."
And then the situation got even worse for the actor, as Grylls wanted him to get the water buffalo head for them to eat.
"Let's try and pull that head out, see what we'll salvage off that," Grylls said, to which Gordon-Levitt incredulously replied, "What do you mean what we'll salvage off that?"
Grylls explained the brain and tongue -- or "anything like that that hasn't had the heat of the sun" -- could be safe to eat later after cooking it.
"The brains? The brains of a mammal?! Oh, there's maggots. We're not eating that dude," Gordon-Levitt said as the camera panned to the insects., disgusted as the camera panned to the insects. "That is really gross."
"The thing I'm scared more of than being eaten by a leopard or falling to my death climbing a rock is some kind of harmful bacteria that my body's not used to, 'cause I'm not from this continent," Gordon-Levitt said to the camera. "This is exactly what I didn't want to do."
Much like his fear of heights, Gordon-Levitt ended up caving on this issue, too, eventually eating some cooked water buffalo tongue.
In order to be positive that they would be safe from the predators of the Savannah, they built a fire-rimmed perimeter around their campsite. However, Grylls doesn't carry a handy dandy lighter, they had to light a fire the old-school way.
Earlier in the show, Grylls told Gordon-Levitt to hold on to elephant feces because it would be useful later. Using a camera lens, elephant droppings and some sun light, they were able to create a fire. That fire triggered childhood memories with his older brother, who died in 2010.
"I'm having flashbacks," Gordon-Levitt said. "I used to do this with my brother, we used to burn up leaves.”
"He passed away 6-7 years ago. I'm his same age now," the actor continued, describing his late brother as a free spirit. "He would love this. He would love this whole thing."
"I don't usually like talking about my brother on TV and stuff, but I feel like there might be some folks watching right now that might be going through it. I remember that helping me in the thick of it was just talking to people who'd also been through it and just knowing that you can survive."
Gordon-Levitt began to tear up as Grylls looked up to the sky and said Daniel was going to help them build the fire.
Perhaps there was no more fitting way to end this survival challenge than having Gordon-Levitt climb a massive cliff to reach the extraction point.
Grylls advised against looking down as they climbed a rope ladder (with each rung being a whopping four feet apart), and eventually, Gordon-Levitt made it safely to the top and cried out, "Rocky, eat your heart out!"
"Man what an experience this whole thing, I feel so fortunate to just get this chance to be invited out here," Gordon-Levitt said as the helicopter picked them up. "This is not something everybody gets to do... I think it kind of kick starts your brain into the next chapter of your identity and I owe it all to Bear."
"Running Wild with Bear Grylls" airs Mondays on NBC.