With thanks to my talented wife, who not only had this idea first, but executed it better.
Lord Plunderfall threw his head back and laughed.
‘Bwa ha ha ha! Your attempts to escape only serve to amuse me.’ He waved a hand towards the children and armed guards emerged from the shadows.
‘Why are you doing this?’ said Freddie.
‘Why?’ said Lord Plunderfall. ‘You ask me why? Well, the answer is quite simple. I seek to destroy the entire world because I am pure evil and wish nothing more than the death of all humanity. Bwa ha h...’
‘Really?’ interrupted Bertha. ‘That’s it? Because that seems a bit improbable.’
‘Improbable?’ thundered the dark figure uncertainly.
‘Yes,’ said Freddie. ‘It’s not all that convincing as a motive. I mean, if you destroy the entire world, where will you live?’
‘I...’ Plunderfall hesitated. ‘Never you mind. I am a force of pure malignancy and I shall tear apart the very...’
‘And if you kill everyone in the world,’ said Bertha, ‘where will you get your food from? Are you going to run your own farm? Is having a smallhold part of your masterplan?’
‘I don’t...’ He seemed to be sweating under his metal mask. ‘That is...’ Freddie shrugged.
‘It just doesn’t seem like you’ve thought it through, you know?’
‘Exactly,’ said Bertha. ‘And I’m sure there’s a more practical material you could have made that mask out of. I imagine the metal edges really chafe.’