Continuity mistake: Martin goes out to a baseball game with a famous writer that Frasier and Niles admire. While he is out, they read one of his books he accidentally left behind. When the author returns, he ends up holding the pages of the book in his hand, whilst standing in front of the fireplace. In one shot he is holding them in his left hand, but when the view cuts to another angle, he has them in his right hand. This occurs just before he goes outside to throw the pages off the balcony.