No but seriously. This scene is adorable. [https://www.youtube.com/watch?v=winO73-gDnc] David Tennant hadn’t actually seen Billie Piper since they recorded the
soul destroying scene at Bad Wolf Bay. They kept Billies parts out of his scripts, out of all the read throughs so it as a total surprise for him. So that face he makes at Donner isn’t just confused Doctor, it’s confused David.