Following the end of his marriage, documentary filmmaker Dean decides to move into an Airbnb, where he unexpectedly encounters Marcel, a charming one-inch-tall talking shell who resides with his grandmother, Nana Connie, and Alan, his pet ball of lint. Inspired by Marcel's quirky outlook on life, resourcefulness, and curiosity about the world, Dean starts filming Marcel's everyday adventures, which primarily involve gathering materials from the backyard to sustain himself and Nana Connie. Nana Connie, although wise, is struggling with dementia while tending to her garden with the help of friendly insects. The bond between Marcel and Connie is further enriched by their shared enjoyment of 60 Minutes and their admiration for Lesley Stahl.
As Dean posts his initial video featuring Marcel on YouTube, it rapidly gains traction, turning into a cultural sensation. Although flattered by his newfound fame, Marcel feels a deep sense of loss, as his family is not present to share in the joy. Marcel reminisces about the vibrant community of shells that once inhabited the property, including his mother, father, brother, and aunt. This community disappeared after the property’s former owners, Mark and Larissa, had a fight that led to the shells inadvertently being packed into Mark's suitcase during his move, leaving Marcel and Connie alone.
Determined to reunite with his family, Dean assists Marcel in hosting a livestream to seek help in locating them. The livestream attracts a significant viewership, but when Marcel reveals his location, the house becomes a magnet for influencers rather than genuine helpers. Marcel becomes disenchanted by this development, feeling that many viewers are more interested in being connected to him than actually assisting in his quest.
The mounting attention begins to take a toll on Marcel, who grows increasingly anxious about Connie's declining health. He persuades Dean to take him on a journey around the city in search of Mark’s car but is overwhelmed by the vastness of the world outside his home. After realizing that finding the car may prove impossible, Marcel returns home only to discover that Connie has fallen off the top of a washing machine and cracked her shell. He takes care of her wounds and becomes more protective of her.
The 60 Minutes team reaches out to feature Marcel in a cover story, but he hesitates, concerned about the potential impact of so much attention on Connie's well-being. Conflicted, he reveals his feelings to Connie, who, despite her fast-deteriorating state, encourages him to embrace the opportunity in the hope that it will help him find his family. With a heavy heart, Marcel eventually consents to the interview.
As the day of the broadcast approaches, Connie's condition worsens. She and Marcel are both excited to meet Lesley Stahl, who is part of the 60 Minutes crew setting up in their living room. After Marcel and Dean participate in the interview, they face a heartbreaking discovery: Connie passed away during the filming. Marcel lays her to rest in her beloved garden, which marks a poignant turning point in his journey. Meanwhile, Dean makes the decision to move into a new apartment.
The 60 Minutes team later reaches out to Dean with hopeful news, having located Larissa in Guatemala, who engages in a confrontation with Mark upon their meeting. Marcel urges the crew to check in Mark’s sock drawer, where the long-lost shell community is finally found. This reunion leads to a proper farewell for Connie. As Dean adjusts to his new life and begins dating again, Marcel reflects on his journey, often returning to the laundry room window to feel the wind passing through his shell—a beautiful and soothing reminder of his beloved grandmother.
In a heartwarming close, Dean introduces Marcel to his new apartment, building upon the foundation of their unique friendship.
