'The Wrong Box,' a novel by Robert Louis Stevenson co-written with his stepson Lloyd Osbourne, is a dark comedy published in 1889. The story revolves around the Finsbury family and a mix-up with a tontine, a financial agreement where the last surviving member inherits the entire fortune. The novel's humor stems from a series of misunderstandings, mistaken identities, and the absurdity of the characters' attempts to outwit one another. Michael Finsbury, a lawyer, and his cousin Morris find themselves entangled in increasingly ludicrous schemes as they try to manage the situation to their advantage, leading to a series of farcical events.

The narrative's charm lies in its witty dialogue, eccentric characters, and satirical take on Victorian society's obsession with wealth and status. Stevenson's writing is sharp and engaging, capturing the reader's interest with its blend of suspense and comedy. Despite its lighthearted tone, the novel subtly critiques the moral and ethical dilemmas faced by the characters, making it a layered and enjoyable read. 'The Wrong Box' remains a testament to Stevenson's versatility as an author and his ability to craft a compelling story with humor and insight.