New Zealand government deploys nude 'porn actors' in web safety ad

Government TV ad is latest in a series of striking public service announcements using humour to tackle tricky subjects

It's a scene out of every parent's - and teenager's - worst nightmare: two adult-film actors turn up naked at the front door, to tell a stunned mother: Hiya ... your son's been watching us online."

The sudden appearance of a smiling but nude Sue and Derek has become something of a sensation as part on an unusual series of TV ads by the New Zealand government about internet safety for young people.