Smilin' Through is a 1919 play by Jane Cowl and Jane Murfin, written under a pseudonym, Allan Langdon Martin. Cowl also starred in the play in a double role and co-directed it with Priestly Morrison. Smilin' Through was produced by The Selwyns and opened at the Broadhurst Theatre on Broadway on December 30, 1919. It included in the cast Orme Caldara as Kenneth and Jeremiah Wayne, Henry Stephenson as John Carteret and Ethelbert D. Hales as Dr. Owen Harding. Scenic design was by Joseph Urban. The play was a popular hit and ran for 175 performances. It also played for a long run on the road, and was one of Jane Cowl's greatest commercial successes.

The story is a sentimental romantic tale of a young Irish woman, Kathleen Dungannon. Her romantic attachment to Kenneth Wayne is opposed by her adopted father John Carteret, who bears the painful memory of his thwarted love for her aunt, Moonyean Clare. Moonyean visits John as a ghost. The roles of Kathleen and Moonyean were both played by Jane Cowl.