On November 23 the 50 year anniversary episode will be shown simultaneously on the BBC and BBC USA.
It is called:"The Day of the Doctor".
This will be the biggest episode ever.
All the old enemy's of the Doctor are in it.
And the Doctor will meet his former body and future body.
When the Doctor is mortally wounded he will regenerate.
At least one of my favourite enemy's is in it,the Daleks.
One big name in this special episode is John Hurt.
Here a few trailers.
This is the first trailer. http://www.youtube.com/watch?v=7z6FMCqYrBo
The second. http://www.youtube.com/watch?v=7z6FMCqYrBo
A teaser trailer. http://www.youtube.com/watch?v=9LnMfKjswhY
A tv trailer. http://www.youtube.com/watch?v=Mkq8pnvsnQg