10 well the Doctor, Donna and Martha (because she was in the TARDIS when it suddenly took off) land on this planet where a war has been going on for generations and they get new soldiers by basically cloning themselves (in a process where apparently you can get either a boy or a girl no matter who you're cloning...) so they clone the Doctor. The Doctor is none too happy about it because he does not approve of Jenny (as Donna calls her) because she acts so much like a soldier, also because, he tells Donna, after having lost a family before he doesn't think he's ready to have a daughter
(essentially, very broken down got all that? I'll continue on the next post )