This is the Death’s-head Hawkmoth, Acherontia atropos. So called because marking on the thorax looks a bit like a skull.
It features on the poster for Silence of the Lambs although, disappointingly, they edited the image to make the skull much more obvious.
The resemblance is (presumably) pure coincidence, but along with the large size, dark colours, and habit of squeaking audibly when disturbed, it it has given the moth a particular sinister aura, reflected in its Latin name. In Greek mythology there are three Fates: Clotho, who spins the thread of life, Lachesis, who measures the thread, and Atropos who ends the life of each mortal by cutting their thread at the ordained moment.
Which is a hell of a symbolic burden to place on the shoulders of an impressive but harmless moth. [do moths have shoulders?]
They are also known for raiding the hives of honeybees. Which seems suicidal. No-one seems quite sure why they don’t get stung to death; suggestions include the fact that they are covered in hair and scales; that they may have some resistance to bee venom; and, most intriguingly, that they smell like bees.