Season 1 of Welcome to Eden follows the hair-raising journey of a group of adolescents. Zoa (Amaia Aberasturi), Instagram royalty África (Belinda Peregrín), Charly (Tomás Aguilera), Aldo (Albert Baró), Ibón (Diego Garisa), and 95 others receive an invitation to the product launch of the decade — which quickly gives way to a sci-fi-esque experiment.

Aldo is among the characters more eager to hatch an escape plan. He hides in a boat he hopes will take him away from the island. In an unexpected twist, he gets shot and killed by Brenda (Claudia Trujillo). Zoa decides that it's time to make the dystopian nightmare stop once and for all in the Season 1 finale. Charly, another Eden participant ready to jump ship, bids farewell to Maika (Lola Rodríguez), a girl interested in dating him.

The group of newcomers tries to leg it the same day a new intake of blissfully unaware party-goers would arrive. Charly reaches the boat that transported the new crowd without any complications. Elsewhere, Bel (Begoña Vargas), Zoa's love interest, gets into a brutal altercation with Nico (Sergio Momo). Regardless, she promises Zoa that she will help her, Charly, and Ibón get hold of diving suits — and she promptly follows up on her word.

Zoa makes some headway with the escape plan, which is when Ulises (Alex Pastrana), an Eden participant with a great deal of seniority, tries to attack her. Ibón intervenes, killing Ulises on the spot.

Just as Zoa is about to take up her much-deserved spot on the boat, she notices a frightening anomaly. Her sister, Gaby (Berta Castañé), is among the new guests arriving at the island. Season 1 of Welcome to Eden ends on a cliffhanger. It's uncertain whether Zoa chooses to save her life or her sister's.