The Slitheen put every single Dr Who monster to shame. They are 8ft tall, green and have big cute eyes. But beware, they're deadly and hide inside fat humans.
Infiltrating 10 Downing Street was genius! The political lady Harriet Jones, MP for Flydale North, was a marvellous character to add. I'm glad she came back in 'The Christmas Invasion' and again in 'The Stolen Earth'. Penelope Wilton is a terrific actor and I am so glad she was in it.
The episode ends on a cliffhanger where Rose and Harriet are about to be killed, Jackie is about to be killed and the Doctor is about to be killed.