A work which has a meaning behind the surface meaning is -

Allegory is a literary form in which one story is told in the guise of another story.
In other words, an allegory is a story of double meanings.
Allegory, a symbolic fictional narrative that conveys a meaning not explicitly set forth in the narrative.
Allegory, which encompasses such forms as fable, parable, and apologue, may have meaning on two or more levels that the reader can understand only through an interpretive process.
[Source: An ABC of English Literature - Dr M Mofizar Rahman and Britannica]