The terrible danger the universe is in allows the Doctor's future self to manifest and assist him in the form of the mysterious Watcher. The two fuse at the story's climax, allowing the new Doctor to appear.
Please read the following before uploading
Do not upload anything which you do not own or are fully licensed to upload. The images should not contain any sexually explicit content, race hatred material or other offensive symbols or images. Remember: Abuse of the TV.com image system may result in you being banned from uploading images or from the entire site – so, play nice and respect the rules!