Michael Stuhlbarg as “Hamlet,” with Lauren Ambrose as Ophelia, in a production directed by Oskar Eustis at the Delacorte Theater in Central Park.

It is believed that if the word MACBETH is spoken anywhere near a theater or during a play that the play will end in tragedy and the theater will be faced with series of badluck!! This superstition is believed to have come from the three witches singing and its believed those words curse the theater or play.
Walking under a ladder is another big susperstition that people believe in.
“If you walk under a ladder, the wrath of the gods will be upon you. Should you forget and do so, quickly cross your fingers or make a wish.
Origin. A ladder leaning against a wall forms a triangle with the wall and the ground. This triangle signifies the Holy Trinity and to enter into the sacred enclosed area is a punishable offense. Also, crossing through this forbidden zone may weaken the powers of the gods and unleash the powers of evil spirits.”
The above preference is a quote from http://http://www.trivia-library.com/a/origin-of-common-superstitions-walking-under-ladders.htm

Broken Mirrors are also a sign of bad luck coming your way. The superstition is an old one and has managed to keep its strength over the years. In fact, many superstitions exist for mirrors but the particular beliefs centering around broken mirrors are the most common today.
Mirrors are thought to have two supernatural abilities: