The Light Fantastic A Discworld Novel #2 Terry Pratchett 1986
What shall we do?' said Twoflower.
'Panic?' said Rincewind hopefully. He always held that panic was the best means of survival.
As it moves towards a seemingly inevitable collision with a malevolent red star, the Discworld could do with a hero.
What it doesn't need is a singularly inept and cowardly wizard, still recovering from the trauma of falling off the edge of the world, or a well-meaning tourist and his luggage which has a mind (and legs) of its own.
Which is a shame because that's all there is...