‘Happy birthday, sis!’ Rae thrust a present into Eva’s hand.

Eva tore into the shimmering fish-skinned wrapping paper.

‘A Mother-of-Pearl travel hairbrush! Thanks!’

‘A must-have for your upcoming mission!’ Rae’s smile was as wide and bright as the pearl gift she’d bestowed upon her sister.

‘You’re more excited than me,’ said Eva.

Rae, a year older, had just completed her mission. She’d been so immersed in it that Eva had barely seen her. Strangely, she’d hardly spoken about it.

Missions were set by the elders when mermaids turned eighteen. Rae had been tasked with collecting discarded plastic.

‘Let’s see what your mission is!’