It was stinking hot in the crowded Cessna Caravan. Wedged in between a young Italian nun and an old woman carrying a live chicken, Mia undid her bandana and opened the top of her shirt. The roar of the single prop made conversation impossible, and she fell into a stupor. In fact, she did not wake until they were bumping across Timbunke’s grass airstrip.

‘Are you all right?’ the nun asked when at last the engine shut down. ‘You were calling out in your sleep.’

‘It must have been a dream,’ Mia apologised. ‘I’ve come a long way.’

Outside, a large group of men was waiting to meet the plane. The nun turned to Mia with concerned grey eyes.

‘There is no hotel in town. Where will you stay?’

Mia gratefully accepted Sister Sofia’s invitation to stay the night at the Catholic mission where she worked.

Kevin, the middle-aged Australian mission manager who picked them up, was less welcoming, and muttered something about tourists. After heaving Mia’s luggage into the back of the old green Land Rover, he drove them down a muddy track. Children playing in flanking palm groves waved cheerfully and Sister Sofia waved back.

‘So innocent, so sweet,’ she sighed, making Mia wonder if she was hankering for children of her own.

‘I caught that one in the petrol store last week,’ muttered Kevin, nodding at a tall boy in tight shorts. ‘If he’s innocent, then I’m a bloody saint.’

A compound of corrugated iron buildings surrounded by razor wire fencing came into view. In contrast to the leafy open grandeur of the Ford Mission, it looked depressingly under siege.

‘Can’t be too careful around here,’ Kevin said, pulling up in front of high steel gates festooned with more razor wire. ‘There’s a reason temptation’s in the Lord’s Prayer.’

‘And forgiveness, Kevin,’ said Sofia gently. ‘Don’t forget that.’

While Kevin unlocked the gates, she explained the mission’s purpose was both educational – running a local primary school – and pastoral, working to strengthen the community. There were eight nuns in residence, all local women except Sofia, and the mother superior, Agnes, who was Kevin’s sister.

She was on the veranda, snipping basil from a pot, when they pulled up beside the main building. An austere-looking woman with short grey hair, her blue eyes were clear and kind, and straightaway, Mia felt that she could trust her.

A few of the other nuns came out to welcome them, and they sat down to hot sweet tea and oat cake. Mia had begun explaining that she was heading upriver to Papua when Kevin cut in loudly.

‘But you can’t just wander around sightseeing on your own. It’s asking for bloody trouble.’

‘I appreciate your concern, Kevin, but I’m not a tourist.’

When she explained her purpose and destination, Agnes’ eyes lit up.