Several of Agatha Christie's novels take their title from a well-known nursery rhyme. Sometimes the first line of the nursery rhyme provides the book title as in “Hickory Dickory Dock” and “One, Two, Buckle My Shoe.” Sometimes there is just a reference to the nursery rhyme , as in “Crooked House” or “Five Little Pigs.” In this case "Sing a Song of Sixpence" is the nursery rhyme, the second line of which provides the title, “A Pocket Full of Rye.”

Christie’s “A Pocket Full of Rye” is one of her Miss Marple stories, published in 1953 and then adapted several times for radio and television. In this case the mystery uses elements from each of the four main verses of the nursery rhyme which run as follows:

Sing a song of sixpence,/ A pocket full of rye./ Four and twenty blackbirds/ Baked in a pie.

When the pie was opened/ The birds began to sing;/ Wasn't that a dainty dish/ To set before the king?

The king was in his counting house,/ Counting out his money;/ The queen was in the parlour,/ Eating bread and honey.

The maid was in the garden,/ Hanging out the clothes,/ When down came a blackbird/ And pecked off her nose.

The “rye” reference is to what was found in the pocket of the first murder victim in the story; the recurring blackbirds have to do with a gold-prospecting scam concerning at the Blackbird Mine in South Africa. The other elements of the rhyme connect with unpleasant deaths involving other characters as the plot progresses.

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