Stephen is a man plagued by agoraphobia, that overwhelming fear of leaving his familiar surroundings, which has kept him confined to his flat for nearly a year. His daily life is meticulously structured around routines that provide him a sense of control and comfort. However, everything changes when he unexpectedly discovers an infestation of mice in his kitchen cupboards. This intrusion throws his carefully balanced routine into disarray, leaving him contemplating whether to venture outside to buy mouse traps. Yet, the mere thought of opening the door fills him with anxiety, so he spends his days reminiscing about the events that led to his current isolated existence, with objects in his flat triggering flashbacks that reveal the story of his past.
Flashback to approximately one year earlier, and we see Stephen [portrayed by Richard Ayoade] embarking on a European sightseeing holiday with his friend Bunny, played by [Simon Farnaby]. Heartbroken after being "friend-zoned" by the woman he loved, Stephen joins Bunny on this trip to distract himself from his pain. They visit an array of unusual museums that Bunny finds dull, as Bunny's primary focus seems to be seducing women, not sightseeing. During a meal at a seafood restaurant in Poland, they meet Eloisa, a charming Spanish waitress with whom Bunny strikes up a playful flirtation. Eloisa has recently ended a relationship and is planning to return to Spain for a fiesta. As a jest, Bunny wagers and wins the restaurant's delivery car, prompting them to invite Eloisa to join their journey to Spain.
Their trip takes them to a hostel in Switzerland, where Stephen plans to ask Eloisa out on a date. However, his hopes are dashed when he learns that Eloisa has already begun a sexual relationship with Bunny. Upon arriving in Spain, Eloisa reunites with her brother Javier, an aspiring matador. Bunny, ever adventurous and impulsive, decides he wants to participate in bullfighting. He asks Javier to teach him the craft, leading to a memorable scene in which Javier shows Bunny a prized matador suit, carefully displayed in a cabinet. Bunny later steals the suit, but soon loses it in a gamble.
Meanwhile, Eloisa and Stephen grow closer, and they share a romantic night together. The morning after, Bunny's reckless behavior comes to light when he reveals the stolen matador suit, prompting Stephen to urge him to reconsider his actions and accompany him as Bunny prepares to leave Spain. Unfortunately, Bunny’s obsession with bullfighting escalates, and he sneaks into a field during a bullfight, attempting to challenge a bull himself. Tragically, the bull kills Bunny, an event that leaves Stephen devastated and traumatized.
This sequence of events is the turning point for Stephen. His guilt over Bunny's death and his inability to cope with the trauma lead him into full-blown agoraphobia, trapping him in his flat and withdrawing from all social life. The story recounts that his mind often drifts to conversations with Bunny’s ghost, who reassures him that Bunny's death wasn't his fault. Bunny also encourages Stephen to reach out to Eloisa. These ghostly dialogues serve as a catalyst, providing Stephen with the courage and hope he needs to confront his fears. In a moment of self-realization, Stephen picks up the phone and reaches out to Eloisa, taking the first step towards overcoming his anxiety and venturing outside once again.
Throughout the film, we are invited into Stephen's reflective mind, understanding how past events, heartbreak, and grief have intertwined to shape his present-day struggles. The narrative emphasizes themes of trauma, regret, and the path toward forgiveness and healing, culminating in the possibility of new beginnings, no matter how daunting they might seem.
