Judy Parfitt, the clenched matron of the Broadway thriller, Night Must Fall, will leave the spell of Matthew Broderick's psychopathic character May 30.

The British actress known for her classy turns in "The Jewel in the Crown" and "Dolores Claiborne," will return to her native England after her Broadway debut experience. Paddy Croft, understudy for Mrs. Bramson, will assume the role June 1.

The run of the Emlyn Williams potboiler was already longer than Parfitt or anyone else expected: The limited-run staging by National Actors Theatre was supposed to end April 18 because of a prior commitment by Broderick.

Good reviews for the John Tillinger-directed revival and Broderick withdrawing from Hartford Stage's June run of The Death of Papa, by Horton Foote, resulted in the extended run.

Night Must Fall transferred from the Lyceum Theatre to the Helen Hayes April 20 and is expected to continue into July. Night Must Fall began previews on Feb. 2 and opened March 8 at the Lyceum, with Broderick, Parfitt, Pamela J. Gray (later replaced by J. Smith-Cameron, known from As Bees in Honey Drown), Michael Countryman (Nine Armenians), Seana Kofoed, Patricia Kilgarriff and Peter McRobbie.

Actress Croft appeared on Broadway in Major Barbara, Crown Matrimonial and The Prime of Miss Jean Brodie. In addition to Off-Broadway credits in Grandchild of Kings, Hogan's Goat and Shadow of a Gunman, she appeared regionally at the Guthrie Theatre, Hartford Stage, the McCarter Theatre and elsewhere.

Tillinger's busy 1998-99 directing season has also included Getting and Spending and The Exact Center of the Universe.

For tickets and information on Night Must Fall call (212) 239-6200. Student rush tickets are available for $10.