promises to be must-watch TV. ' />

The upcoming series of NZ's Next Top Model promises to be must-watch TV as Spy can reveal trips to Melbourne and Phuket are on the cards and All Black Dan Carter will make a special guest appearance.

An inside source on the show said a Water For Everyone nutrition lesson is scheduled to shoot in July with Carter playing the role of entrepreneur. That will no doubt get the heart rates of the young models racing. Of course, producers will also be expecting a huge ratings hit with that episode.

Not that producers are giving anything away. Network exec Andrew Szusterman would only say: "We can't comment about guests on the show."

The All Black legend, who will be in the middle of rugby season commitments, is a shareholder of Premium New Zealand Trading Company alongside Richie McCaw and Ali Williams, who appeared in a similar product placement episode on rival reality show The Apprentice, where they promoted their Water For Everyone brand.

Celebrity hairdresser Paul Serville is also expected to make a guest appearance on Top Model in a GHD hair straighteners makeover at his Newmarket salon. But it is the underwater and body art photo shoots that will probably be the most challenging for the girls.