WESTPORT — Mystery writers will dissect the literary genre of whodunits — also, perhaps, how they dunit and what they dunit with — during a July 9 program at the Westport Country Playhouse.

The event, “Summer Thrillers: A Mystery Author Discussion,” will take place at 2 p.m. Sunday, July 9, in the Lucille Lortel White Barn, adjacent to the theater, 25 Powers Court.

Tickets to the program are free, but must be reserved in advance by clicking here.

The discussion is planned in conjunction with the theater’s staging of a new adaptation of “Dial M for Murder,” which will be performed July 11-29.

Three writers are scheduled to participate: Christin Brecher, author of “Photo Finished;” Edwin Hill, author of  “The Secrets We Share,” and Andrea Penrose, author of “Murder at the Serpentine Bridge.”

There also will be a question-and answer period with the writers, who will be available to sign copies of their books offered for sale.

For more information, call the Westport Country Playhouse box office at 203-227-4177, or visit the theater’s website.