Trifles is a lousy mystery. All the action took place before the curtain went up

Trifles is a lousy mystery. All the action took place before the curtain went up. Almost in the beginning, on the third page, we find out ‘who done it.’ So there isn’t really much reason for us to sit through the rest of the play.” Discuss this view. Is there credibility to this, or is there more to this play than ‘who done it’?