Oak Street's 'Black Coffee' potent entertainment - Oct. 2-4

photo Justin Bolinger, left, as Dr. Carelli, and Coylee Bryan as Caroline Amory confer during a scene from "Black Coffee," which opens Friday at the Oak Street Playhouse.

IF YOU GO• What: "Black Coffee."• When: 7:30 p.m. Friday, Saturday and Oct. 2-4; 2:30 p.m. Oct. 5.• Where: Oak Street Playhouse, corner of Vine and Lindsay streets (in First-Centenary United Methodist Church).• Admission: $12 adults, $10 seniors and groups, $5 students; all adult tickets $10 opening night and Girlfriends Night Out (Oct. 2).• Phone: 423-756-2428.• Website: www.oakstreetplayhouse.com.

Mystery can be intriguing but also entertaining.

That's the story with "Black Coffee," the Agatha Christie mystery that opens in the Oak Street Playhouse's Flo Summitt Theater on Friday, Sept. 26.

"It's entertainment as well as mystery," says director Brenda Schwab. "It has humor but also some quirky, odd characters."

The story focuses on British physicist Sir Claude Amory, who has come up with a formula for an atom bomb. In the first act, he is poisoned - in his black coffee, of course. That brings in Hercule Poirot, one of Christie's most famous sleuths, who, naturally, solves the case.

It's how he solves the case that gives the story its character, according to Schwab.

"I like this one," she says, "because all these red herrings are out there. You [do] not know who does it until the last few pages. Everybody has a reason [to kill him]. That's what's fun about this one."

Although Poirot, whose character was Belgian but appears French, appeared in 33 of the mystery writer's novels and more than 50 short stories, "Black Coffee" is her only play in which his character appears.

The play has 13 characters, including Sir Claude's sister, son, daughter-in-law, niece, secretary, and, of course, butler, plus a visiting Dr. Carelli, so there are a variety of suspects.

Schwab previously directed another classic Christie mystery, "Ten Little Indians," at Oak Street Playhouse in 2013.

"I did not know this one," she says of "Black Coffee." "But I like these characters ... more than those in 'Ten Little Indians.'"

The play runs for two weekends at the theater.

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