Susan "Sue" Trinder is a fingersmith (British slang for thief) who lives in the slums of London with a baby farmer (person who looks after unwanted babies) Mrs.Sucksby. When a once rich man, who gambled all his money away, presents them with a scam that has a payout of 40,000 pounds, Sue signs on to swindle rich Maud Lilly. Maud is an orphan who lives with her uncle, but what exactly is going on in the Lilly house? Sue will pose as Maud's maid so that Mr.Rivers (the gentleman) can get close to and eventually marry her. Their plan is to put Maud in the madhouse and take the money for themselves. All goes astray though when Sue falls in love with Maud. And the question is: Who can you trust?