moffet is known to plan his stories out years in advance, so im sure it could all be possible. So I went back and watched it frame by frame, and at first I thought it was just a shadow from the car. THEN IT MOVED! You can clearly see the outline of an arm move when you go frame by frame. Who or whatever it is, is there from the time they sit down for the picnic to the time they burn his body..... In Classic the Masters TARDIS was hidden as a beach hut! So it could be The Master!!