In the opening scene of Episode 7 of "Percy Jackson and the Olympians," Percy steps into the shadowy realm of the mattress store, overseen by the nefarious Procrustes, also known as Crusty, Poseidon's miscreant son and Percy's reluctant stepbrother. Crusty, guardian of the underworld portal hidden within the store's labyrinth of mattresses, attempts to lure Percy into a false sense of comfort. But Percy sees through the ruse and, with a deft move, thrusts Crusty onto one of the beds. Instantly, the mattress coils around him, immobilizing him.
At this juncture, Annabeth and Grover materialize, joining Percy in his predicament. Together, the trio utilizes the store's secret portal to descend into the Underworld, a realm of chilling desolation and eternal night. There, they encounter Chiron, a spectral figure resembling the Grim Reaper. Since they are still living, he commands the fearsome three-headed Cerberus to attack them.
For a seemingly endless stretch, Cerberus hounds them through the bowels of the Underworld. In the heat of the pursuit, Grover loses his orb, forcing Annabeth to rely on Poseidon's orb to escape the clutches of the Underworld. Eventually, Percy and Grover find themselves in a desolate, desert-like landscape where Cerberus finally ceases his relentless pursuit.
However, Grover's misfortune continues as his flying sneakers suddenly malfunction, dragging him perilously towards the sea. Swiftly, Percy swings his sword, slicing through the air to rescue his friend. As they catch their breath, Percy discovers the stolen master bolt of Zeus hidden in his backpack. Reasoning that Ares, who had given him the bag in St. Louis, must be involved, they realize they are on the trail of a larger conspiracy.
Yet, their quest is not complete. Percy is still in search of his mother. Together with Grover, they brave the Underworld once again, seeking audience with Hades. The Lord of the Underworld greets them with a feigned warmth, offering them refreshment. But Percy's impatience gets the better of him, and he demands to know the whereabouts of his mother.
Hades acquiesces, leading Percy to a chilling sight - his mother, transformed into a statue of gold. He offers a bargain: if Percy can retrieve his helm of darkness, he will restore his mother to life. He reveals that the helm was stolen on the same day as Zeus's master bolt, pointing to a larger conspiracy at play.
As the pieces fall into place, Percy realizes that Kronos, the God of Evil and Time, and the father of the gods, is the culprit. Kronos's ambition to wage war with the master bolt in his grasp has Hades on edge. He proposes a new deal, promising to protect Grover, Percy's mother, and Percy himself if he surrenders the bolt to him.
However, Percy's sense of honor prevents him from betraying Zeus. He rejects Hades's offer, choosing instead to uphold his loyalty to the gods. With resolve, Percy and Grover take their orbs and depart, leaving Hades behind as they make their way to the beach, determined to continue their quest and unravel the mysteries that lie ahead.
Throughout this episode, a shadowy incident from the past slowly emerges into vivid life. Because of his eccentricity, Percy finds himself on the brink of a new school adventure, orchestrated by his doting mother, Sally. To ease the transition, she escorts him to a cozy cafe, a haven of warmth and understanding before bidding him farewell.
But as Percy sulks in a corner, a curious sight unfolds. Sally is engaged in a whispered conversation with Poseidon, a godly figure cloaked in mystery. She pleads with him to reveal himself to her son, but he replies with a reassuring smile, promising that the time will come when Percy has firmly grasped his identity and his place in the grand tapestry of the world.
Finally, upon reaching the inviting shores of the beach, Percy and his loyal friend Grover are delighted to spy Annabeth, patiently awaiting their arrival. The episode draws to a climax as Percy catches a glimpse of Ares, the god of war, stalking towards him, a portent of challenges and adventures yet to unfold.
