Cullen turned to prose by reworking Euripides' tragedy Medea. The staging never materialized, but Cullen published the text in The Medea and Some Other Poems (1935). He edited Caroling Dusk: An Anthology of Verse by Negro Poets (1927) and produced the clumsy, stilted novel One Way to Heaven (1932), a blend of vigorous characterization and leaden satire. As his health deteriorated from hypertension, he composed light verse, including The Lost Zoo (1940), about the animals that Noah failed to load, and My Lives and How I Lost Them (1942), based on the activities of his pet, Christopher Cat.
Following a lecture engagement at Fisk University in 1940, Cullen returned to Harlem to collaborate on an adaptation of Arna Bontemps' novel God Sends Sunday (1931). Titled St. Louis Woman (1946), the play is the basis for the Broadway musical for which Vernon Duke provided music. Rehearsals were in progress at the time of Cullen's death on January 9, 1946, at Sydenham Hospital in the Bronx. He was eulogized at his father's church and buried at Woodlawn Cemetery. A posthumous collection, On These I Stand (1947), appeared two years after his death.
