After her father's death, 13-year-old Martina is relieved when her grandfather invites her to stay with him for the summer in his caretaker's flat at a mansion block in Pimlico. Martina is captivated by London and the elegance of her surroundings. She is particularly fascinated by wealthy Cecelia Buchanan, an older woman who shares her flat with Luca, a man in his 30s who has befriended her. Martina is drawn into their world, entranced by beautiful possessions and enjoying Cecelia's praise of her artistic talents. She is also captivated by Luca and develops an overwhelming crush on him. As the story unfolds a bewildered Martina witnesses betrayal and a tragic end.