A theatre with entirely reserved seating is sold out for performance and everyone who brought a?

... ticket shows up. The theatre seats 128, the seats are duly numbered 1,2,...,128, and each ticket has the number of the seat the number of the audience is to sit in. The audience enters the theatre one at time. Unfortunately, the first one to enter dose not notice the number of the seat on the ticket and sits in random eat. After that, each person sits in their assigned seat if it is unoccupied, and one of unoccupied seats at random otherwise. What is the probability that the last number of audience to enter gets to sit in their assigned seats?