After being pulled involuntarily by the TARDIS at the end of last week's episode (much to Martha's annoyance), The Doctor, Donna and Martha arrive on the planet Messaline. As soon as they set foot in the underground tunnels, The Doctor's hand is plunged into a cloning machine and creates his daughter.
Interesting points to note;
1. The human fighters say the reason for the fighting is over some "source", which as we discover, is to rejuvenate a tired and dying planet.
2. Donna - who's turning out to be quite a sharp assistant - worked out from the numbers above each section, that the war had only been going seven days, and each soldier was a clone.
3. The Doctor's Daughter was named Jenny - anyone remember a character in "The Dalek Invasion of Earth" by that name? She was a rebel too!
4. The landscape on the surface was reminiscent of a Philip K Dick novel.
5. The source was used to create life, although the humans and possibly the Hath, wanted to use it to destroy the "enemy". Funny how us people don't seem to understand what exactly we're supposed to do with creation!
6. Also, Jenny regenerated (not intended, honest!) right at the end. Now we have two Timelords roaming the universe! Watch out for danger, everyone! 