On a beach near the village of Otara, a portal shimmers into existence. When fully formed, it is a round opening, just over three feet high, through which the view is very slightly different if looked at from the right angles. Someone looking closer might be able to make out the edges, wavering like heat haze.
A few motu fishermen are nearby, hauling in their day's catch. They do not notice the portal immediately, but the sound of their singing carries through it on the breeze.