Database design to record occurences in tv show
I think given the requirements and that at some point you may want additional information that wasn't listed here, I would go with a fully normalized approach.
3 Tables: Guests, Episodes, Episode_Guests
Then depending on if you want to do this for more than one show, another table for Shows(or series).
As Paparazzi mentioned, the Guests table should contain sex.  The Episode table should contain a date.  Also, if you are going to do this for multiple shows, the Episode table should also have a foreign key back to the Shows table.
The Episode_Guests table should record every instance of a Guest appearing on an Episode so all it would need is a foreign key relationship back to guests and another for Episode.