Nell is a young orphan girl raised solely by her grandfather, Mr. Trent, in his 19th-century London antique shop. When Trent defaults on a loan to the moneylender Daniel Quilp, they flee London to escape Quilp's threats, which include forcing Nell into marriage with his elderly assistant, Brass.

Their journey evolves into a quest driven by Nell's hope to find her mother, rumored to reside in a place called "Paradise" within Great Britain. This search persists despite her grandfather's initial doubts. Throughout their travels, Nell and her grandfather confront poverty, danger, and relentless pursuit by Quilp and his associates.

Characterized by kindness, resilience, and a strong sense of responsibility, Nell forms friendships along the way, including with Kit, a former employee of her grandfather's shop who later aids in the search. Her journey uncovers previously unknown family ties, revealing an older brother named Mario and leading to her eventual reunion with her mother, Rosa, in Ireland – a significant departure from the original Charles Dickens novel where Nell dies.

Nell endures significant hardships during this ordeal, including illness and near-starvation, but survives. The resolution sees her grandfather overcoming his personal struggles, the defeat of Quilp, and Nell finding a new life with her reunited family in Ireland.