Juliet is an aspiring English artist who falls deeply in love with the city of Venice and its vibrant culture. Forced by family financial hardship to abandon her formal art education, she takes up a teaching post to support her mother and sister. Returning to Venice years later on an educational pension, she pursues her passion for modern art while facing the looming threat of a global conflict.

Caroline is an editorial assistant for a fashion magazine who previously gave up her dreams of becoming a designer. Facing the end of her marriage and separation from her young child, she receives a mysterious inheritance from her great-aunt. This unexpected gift prompts her to travel to Italy, seeking answers and a chance to rebuild her confidence.

Leonardo is the only son and heir of a powerful aristocratic Venetian family. He possesses a deep appreciation for art and secretly wishes to open a gallery rather than take over his family's business empire. Burdened by familial expectations, he attempts to balance his duty to his heritage with his personal desires and anti-fascist political leanings.

Luca is the modern-day grandson of Leonardo Da Rossi and current head of his family's business. He carries his own emotional baggage from a turbulent past marriage but approaches life with charm and curiosity. He takes an active interest in helping Caroline piece together the historical mysteries connecting their families.

The Contessa is a well-respected elite patron of the arts and a Polish émigré of Jewish heritage. Married to an Italian count, she uses her wealth and high social standing to protect avant-garde artists and individuals fleeing oppressive regimes. She acts as a mentor and protector figure for the young expatriates in her circle.

Josh is Caroline's ambitious husband who works as a designer for a fashion house. Dissatisfied with making conventional clothing, he seizes an opportunity to design for a high-profile celebrity tour. He focuses on his own career advancement, often at the expense of his family responsibilities.

Teddy is the six-year-old child of Caroline and Josh. Caught in the middle of his parents' sudden separation, he travels to the United States to spend the summer with his father. His return is repeatedly delayed by illness and global events, causing immense distress for his mother.

Granny is Caroline's pragmatic grandmother and Juliet's younger sister. She provides a stable home environment and encourages her granddaughter to take a much-needed respite in Italy. She suggests Caroline travel to scatter family ashes and solve a lingering mystery.

Hortensia is Juliet's strict and highly proper aunt who chaperones her 1928 birthday trip to Italy. She is highly protective of family reputation and severely disapproves of Juliet interacting unchaperoned with local men. She demonstrates the rigid social expectations of the era.

Hanni is a twelve-year-old Austrian girl whose Jewish family smuggles her out of the country to escape a fascist regime. She relies entirely on the underground network of sympathetic patrons in Venice for her survival and education.

Angelo is a young child whose portrait appears repeatedly in the hidden sketchbooks Caroline discovers. His exact identity and connection to the Da Rossi family form a central mystery connecting the two timelines.

Henry is an American art student studying in Venice who expects to eventually return home to work for his father's automobile company. He forms a close, reliable friendship with Juliet and frequently accompanies her to local events.

Bianca is a young, beautiful woman from a powerful Venetian family. She is betrothed to Leonardo from a young age due to familial arrangements. She expects a life of luxury and status, showing little interest in traditional domestic obligations.

Mr. Sinclair is His Majesty's consul in Venice. He recognizes the strategic value of Juliet's apartment overlooking the harbor and recruits her to secretly monitor shipping activity for the British military.

Imelda is a Spanish art student whose family fled General Franco's regime. She is observant and outspoken, quickly becoming one of Juliet's first close friends at the academy.

Signora Martinelli is Juliet's landlady during her 1939 stay in Venice. She maintains a respectable, traditional boarding house and is highly conscious of neighborhood gossip and propriety.

Vittorio is an associate who works to acquire art for the Contessa. He travels frequently and has extensive knowledge of the underground channels required to smuggle modern art out of hostile territories.

Francesca is a local Venetian woman employed to maintain Juliet's household. While not overly warm, she is highly competent and provides essential domestic support during a period of heavy rationing.

Franz is an Austrian art student at the academy. He holds strong pro-German political views, causing some tension and suspicion among the other expatriate students.

Desiree is a famous pop star who hires Josh to design the wardrobe for her upcoming tour. She represents the glamorous, wealthy lifestyle that draws Josh away from his family in London.