An asteroid is steaming towards Earth and the world's greatest scientists - and Isambard King Kong Brunel - are called together to come up with a solution. Squawkencluck invents a size-changing device which is stolen by the ever frustrating Brunel who intends to use it to make himself taller. In the furore Penfold is accidentally zapped and made massive. Penfold panics and runs away but it's quite hard to hide when you are 1000ft tall. For once the world is relying Penfold to save it so can DM calm the gigantic Penfold long enough for him to deal with the asteroid?