Named after a butterfly species, it details the key events of the life of a Victorian naturalist, William Adamson, at first seemingly struggling to move up in class and settle down with a beautiful, mysterious aristocrat, Eugenia.

When he begins a study of garden ants with the household tutor, Matty Crompton, he discovers the endless layers of interpretation that hide truths (but not The Truth) behind what he has taken for granted about God, science, England, gender, and family.

The novella is notable for its use of blend of postmodern and Victorian fiction, as well as philosophy and science.

The Independent identified Morpho Eugenia as the stronger of the two novellas published as Angels & Insects and in particular hailed Byatt's "gaudy panache and sly Gothic tricksiness.

"[2] The novella was adapted into the movie Angels & Insects in 1995 directed by Philip Haas and starring Mark Rylance as William Adamson and Kristin Scott Thomas as Matty Crompton.