Things that go scrape in the night

Pte. Jem Duggan woke to a finger over her lips, and the terrified face of Sgt. Connolly.

Take this. If we both fire into its eyes it’ll buy enough time to run for the shuttle’, he whispered, handing her a loaded sidearm.

‘Did you alert Spacefleet?’

No time, it’s been up on the roof sharpening its anterior blades for hours -the thing knows we’re the only humans on this planet.’

‘The roof? Are you sure that wasn’t squirrels Sarge?’

That’s what it was! …thank God, I didn’t know this planet had squirrels.’

‘It does. What d’ya think it was?’

Nevermind.’