Martha Kathleen Henry CC OOnt (née Buhs; February 17, 1938 – October 21, 2021) was an American-Canadian actress and director of stage and screen.

Henry caught the attention of Artistic Director Michael Langham, who offered her a spot in the 1962 company based entirely on her performance that day.

[8][9][10] During Henry's first season at the Stratford Festival in 1962, she played Miranda to William Hutt's first Prospero in The Tempest, and Lady Macduff in Macbeth.

A major uproar ensued across the Canadian arts community, and Immigration Minister Lloyd Axworthy denied Dexter a work permit.

[33] Henry was artistic director of the Grand Theatre in London, Ontario, from 1988 to 1995, during which time she programmed a wide variety of contemporary works, including newer plays such as Oleanna by David Mamet, The Rez Sisters by Tomson Highway, and The Stillborn Lover by Timothy Findley.

[34][35][36] Henry's return to the Stratford stage in 1994 as Mary Tyrone in Long Day's Journey Into Night was widely acclaimed, and the production was remounted for the 1995 season.

In his review of the production, J. Kelly Nestruck of the Globe and Mail said "Henry’s performance is a reminder of how much more daringly theatrical her generation of stage actors – she’s now in her 80s – can be".

Notable television roles include Catherine in Empire, Inc.,[46] the prime minister's mother in H2O,[3][47] and the owner of the Chateau Rousseau in Ken Finkleman's At the Hotel.

[54] Henry died of cancer shortly after midnight on October 21, 2021, at her home in Stratford, Ontario, twelve days after her final stage appearance in Three Tall Women.