Ang Kapitbahay is set in a university town where Alex, a shy and innocent college boy, moves into a new apartment complex. Upon his arrival, he is immediately captivated by his next-door neighbor, Rose. She exudes confidence, sensuality, and an air of mystery that intrigues Alex.
As Alex and Rose start interacting, a strong chemistry develops between them. Rose, aware of Alex's naivety, finds pleasure in teasing and seducing him. She becomes both his object of desire and his guide into the realm of grown-up intimacy. Alex, overwhelmed by his newfound sexuality and the thrilling sensations Rose introduces him to, falls deeper into her spell.
However, as their relationship intensifies, Alex begins to notice peculiarities about Rose. He discovers that she has a dark past and might be involved in dangerous activities. Questions arise about her true intentions and motives, leaving Alex torn between his infatuation with Rose and his growing suspicion that he has fallen into a trap.
Mysteries and twists unfold as Alex delves deeper into the secrets hidden behind closed doors. He must navigate a web of deceit, danger, and betrayal to uncover the truth about Rose and protect himself from the impending danger that threatens to consume him.
Ang Kapitbahay explores themes of sexual awakening, temptation, and deception. It takes viewers on a suspenseful journey, blurring the lines between desire and danger, as Alex's innocence slowly transforms into understanding the harsh realities of adulthood.