Actor Joseph Gordon-Levitt tackles Kenya's unyielding terrain with Bear Grylls. Dropped into the elements from a helicopter, Joseph and Bear navigate a perilous rappel, milk a camel for needed hydration, and ascend a massive rock dome that tests Joseph's fear of heights like nothing before. As the duo battles a crocodile for the remains of a water buffalo that is their only hope for dinner, Joseph details his rise to fame and his efforts to honor the memory of his beloved brother.

Actress Keri Russell joins Bear on an epic journey to the Canary Islands off the coast of Africa. After battling the dangerous, rolling rocks of a massive volcano, the duo descend into a mysterious canyon where they source a meager dinner of undigested seeds from a pigeon carcass, and test their luck with a grappling hook to escape the towering canyon walls. Later, after a cringe-worthy breakfast of crickets, Keri and Bear make a daring escape from a mountain peak using a paraglider. Along the way, Keri reveals her path to fame, her love of family, and the playful struggles of co-starring alongside her husband. .

Bear takes Lena on the ride of her life as they paramotor deep into the remote Spanish wilderness. Continuing on foot, they traverse a towering, razor-thin ridge before a dead-end forces a harrowing rappel. After securing a dinner of bone marrow from a goat carcass, the two must cross a lake using a makeshift raft as an unexpected storm wreaks havoc. As they battle the elements, Lena grants us exclusive details of life on "Game of Thrones," her rise to stardom, and her battle to overcome depression.