QUARRY GAP, Pennsylvania — The Lantern Playhouse has canceled the final preview of its fall comedy after two audiences repeatedly laughed, applauded and called warnings several seconds before the corresponding action occurred onstage. The company has delayed opening night by one week and is offering exchanges or refunds for the affected performances.

The playhouse, a 212-seat volunteer theater in a former fraternal hall, had scheduled three low-cost previews before opening Saturday. Thursday's audience included 63 season subscribers and guests. Director Alina Bex said the first early reaction came during an ordinary entrance, when applause began while actor Warren Pike was still waiting behind a closed door.

Similar interruptions followed. Patrons laughed before the setup to a joke, inhaled together before a glass slipped from a sideboard and applauded a dance before the recorded music began. Pike said the responses were not scattered guesses. They rose from different sections of the room and ended as the actors reached the moments the audience had already acknowledged.

The company initially treated the timing as a performance problem. Actors shortened pauses, skipped two lines and entered from opposite wings. The audience adjusted with them. When a prop telephone failed to ring, several patrons turned toward it and laughed at the silence before the stage manager knew the cue had been missed.

No one in the audience reported seeing the action in advance. Patrons interviewed afterward said their reactions felt appropriate at the time but could not explain what they had responded to until the scene caught up. Miriam Rook, who attended with her sister, said she remembered Pike dropping the glass before she watched it leave his hand.

Bex invited 18 people with no connection to the production to a closed rehearsal Friday afternoon. They surrendered phones and received no program. The same pattern developed during the second act. A stage manager comparing the room microphone with the rehearsal video found most group reactions began between three and six seconds before the related line or movement.

Shared expectation can make a theater audience behave like a single social unit, said performance researcher Celia Dorn, who reviewed short recordings at the company's request. One person's laugh or gasp often prompts others before they understand a scene. Dorn said contagion could explain the speed and uniformity of a response, but not why the first visible reaction repeatedly preceded an unsignaled action.

The disruptions have affected the cast as well as the schedule. One actor stopped before crossing a loose section of scenery because the audience shouted a warning. A support brace failed a moment later. No one was injured. The company has since inspected the set, replaced the brace and prohibited further rehearsals with scenery above the actors.

Board chair Dennis Ayer said the playhouse will use the delay to restage entrances and review its sound and lighting controls. Ticket revenue from the opening weekend represents about one-tenth of the company's annual operating budget, but reserves will cover the postponement. Rehearsals without observers have continued normally.

At Friday's closed rehearsal, Bex asked the lead actor, Nessa Cole, to replace the final speech with any sentence she chose and not disclose it beforehand. Cole stood in silence for nearly a minute. The invited audience rose together while she was still thinking, then remained standing without applause.

Cole finally said, 'We have not reached that part yet.' Several people in the front row began to sit before she spoke the word 'yet.' The remainder applauded only after the sentence was complete, and no one could say why they had stood.

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