I should have known better....(SPOILERS)

SPOILER ALERT

I watched "And then there were none" last night - a group of strangers are being knocked off one by one in a gloomy, isolated mansion. Charles Dance is one of the strangers, an amiable retired judge. He gets murdered in turn, then comes back at the end to be revealed as the murderer.

At first I thought "hmmmmm, Charles Dance is in the film and he's not the heavy."

I should have known better...