Rated M for violence.

Here's one that sucked the oxygen out of the studio when we played it. You could hear people not breathing. In fact, there were a handful of people crying as it finished. That's how powerful the content of this ad is.

We found it last year in the early stages of preparation for The Gruen Transfer, and knew right away that we wanted to put this to air. In the UK, where it comes from, it was shown in a very limited cinema run and then online. It's a bit much for TV - that only made us want to show it more.

The ad was the brainchild of Thompson and Dr Michael Korzinski, a director of the Helen Bamber Foundation, which works with survivors of torture and cruelty. Elena is a real person - a patient of Dr Korzinski, and a former sex slave from Moldova. All the dialogue in the ad is actually real, words and ideas taken from the mouths of Dr Korzinski's clients. The ad was made at Thompson's house - written in two hours and shot in three with the help of an ad team

The visual effects used in the ad are worth examining. It's framed so that you see Thompson's face close-up, creating a 'suffocating' effect. It is shot from above, giving the viewer the uncomfortable perspective of the perpetrator. The editing echoes horror movies. The script is a simple and stunning idea, with Thompson's words, "Help me!", resonating most deeply.

It's an impressive piece of film making. But advertising must be effective as well as creative. And interestingly, the panel was divided about whether it's a good ad. Russel Howcroft called it "advertising at its absolute best". However, Todd Sampson said the level of shock employed by the ad went too far, with him feeling paralysed, not knowing what to do after seeing it. There's no call-to-action, no hotline to donate money or get involved.

The aim of the communication, our panel proposed, was to raise the awareness of the issue in the minds of politicians, to move it up a few notches in terms of public consciousness. If that's the case, then Thompson's celebrity factor and the power of the emotion would almost certainly have done that.

At Gruen, we've had to watch it quite a few times. It never gets any easier. We hear what the panel says about call-to-action, but we think it's one of the most unforgettable ads we've ever seen.