Acherontia atropos.

This dropped out of a basket of clean washing I'd just brought in from the garden. It was about 3 inches across, and although not moving much, was still alive. I released it outside. It may be a death's head hawk moth, much featured in horror films and literature. A few years ago I brought in a giant cricket tangled in the bedsheets. Unknown to me it fell out behind the bed and gave me a scare in the night when it popped up! Dangerous times...