When chimney sweep Tom Wasp visits his friend Eliza Hogg in Newgate Prison in January 1863, on the day before she is due to be hanged, he is surprised to be given the only thing of value she possesses and even more surprised when that turns out to be a pawn ticket. Tom's apprentice, twelve-year-old Ned, is disappointed that the pawned item is only a scruffy sailor doll. Some days later, however, they find its hidden secret...