Strange Interlude is a 1923 experimental play by Eugene O'Neill. The play has extensive soliloquies (monologues by characters) and deals with themes of love, loss and the tension between volatile emotions and rational planning. The play tells the story of Nina Leeds who engages in numerous affairs after the death of her fiance before marrying Sam Evans. After learning that insanity runs in the Evans family, Nina aborts the baby and conceives another with Ned Darrell, with whom she accidentally falls in love.
The plot centers on Nina Leeds, the daughter of a classics professor at a college in New England, who is devastated when her adored fiancé is killed in World War I, before they have a chance to consummate their passion. Ignoring the unconditional love of the novelist Charles Marsden, Nina embarks on a series of sordid affairs before determining to marry an amiable fool, Sam Evans. While Nina is pregnant with Sam's child, she learnsa horrifying secret known only to Sam's mother: insanity runs in the Evans family and could be inherited by any child of Sam's. Realizing that a child is essential to her own and to Sam's happiness, Nina decides on a "scientific" solution. She will abort Sam's child and conceive a child with the physician Ned Darrell, letting Sam believe that it is his. The plan backfires when Nina and Ned's intimacy leads to their falling passionately in love.
Twenty years later, Sam and Nina's son Gordon Evans is approaching manhood, with only Nina and Ned aware of the boy's true parentage. In the final act, Sam dies of a stroke before he can learn the truth. This leaves Nina free to marry Ned Darrell, but she declines to do so, choosing instead to marry the long-suffering Charlie Marsden, who proclaims that he now has "all the luck at last."
The meaning of the title is suggested by the aging Nina in a speech near the end of the play: "Our lives are merely strange dark interludes in the electrical display of God the Father!"