According to Samuel Pepys, the boy Killigrew used to volunteer as an extra, or "devil," at the Red Bull Theatre, so that he could see the plays for free.

[1] Before the English Civil War, Killigrew wrote several plays—tragicomedies like Claracilla and The Prisoners, as well as his most popular play, The Parson's Wedding (1637).

The latter play has been criticized for its coarse humour; but it also contains prose readings of John Donne's poetry to pique a literate audience.

Along with Sir William Davenant, he was given a royal warrant to form a theatre company in 1660—which gave Killigrew a key role in the revival of English drama.

[3] Killigrew beat Davenant to a debut, at Gibbon's Tennis Court in Clare Market, with the new King's Company.

Of his last three works, Thomaso is a broad comedy based on Killigrew's experiences in European exile, while Bellamira and Cicillia are heroic romances—but all three are closet dramas, ten-act double plays never intended for the stage.

[5] The tragedy The Pilgrim, apparently never performed, borrows its plot from James Shirley's The Politician and reveals many allusions to Shakespeare.