So is it Fulci's masterpiece?

[Sarah@Cult Labs]

In the tagline, Shameless describes Don't Torture a Duckling as Fulci's masterpiece - a term I've heard a lot of my fellow Shameless fans using in relation to the film.

So what do you all think? Is it, in fact, Fulci's greatest achievement? Or do you favour some of his other work? Perhaps it's his best giallo but not his best film overall? Or perhaps anyone who suggests it's not his masterpiece should prepare for an ass whooping?

Whatever you're opinion, make it known in this thread!