A foil is a person (character) who contrasts and parallels another character in a story or play, usually the protagonist. The foil’s purpose is to illuminate certain qualities (strengths and weaknesses) in the main character or other characters. The foil may be a complete opposite or very similar with one crucial difference.

Difference between foil and antagonist. The foil is not necessarily the antagonist, who is in direct conflict with the protagonist. The antagonist’s actions oppose the protagonist, whereas the foil’s character opposes the protagonist’s.

Examples

• Sherlock Holmes and Watson (on the same side, working together)
• Harry Potter and Draco Malfoy (similar situations, opposite choices)
• Romeo and Mercutio (both House of Montague)
• Jay Gatsby and Tom Buchanan
• Dr. Frankenstein and Frankenstein’s monster (both are literary foils to each other)

A subplot can act as a foil to the main plot by showing an opposing situation, such as in metafiction or the “story within a story” motif. (More on motifs here.)

Don’t let the foil foil you!

Origin of the term “foil”

The term foil comes from an old practice where gemstones were backed by tin foil to enhance their brilliance.

A few words about “frame story”

(Section added April 26.)

A frame story can be used to structure a novel that is intended for one audience but whose story would be misinterpreted as content for another audience.

For example, a book (or movie) that is decidedly for adults but contains a story that involves a child protagonist would be considered a YA novel by agents and publishers (and even readers) and would be rejected because the nature of the content wouldn’t fit the YA market.

Such a story can be written so that the adult protagonist begins and ends the story, thus framing the child portion of himself within. Opening with an adult protagonist would align the book and subject matter with its intended market.

“A frame story (also known as a frame tale or frame narrative) is a literary technique that sometimes serves as a companion piece to a story within a story, whereby an introductory or main narrative is presented, at least in part, for the purpose of setting the stage either for a more emphasized second narrative or for a set of shorter stories. The frame story leads readers from a first story into another, smaller one (or several ones) within it” (Wikipedia).

An interchange between Romeo (protagonist) and Mercutio (foil)

Mercutio (top of the stairs)
Romeo (striped sleeves and purple cape)

ROMEO AND JULIET — Franco Zeffirelli

All the posts: Components of Literature A to Z

G is for Guts as in Grit

See also: A is for Antagonist in April

Sources

A Glossary of Fiction Terms, Scribendi, scribendi.com

Foil, literarydevices.com

Glossary of Fiction Terms, Online Learning Center, highered.mheducation.com

Wikipedia (foil, metafiction, subplot), wikipedia.org