Mabel Mynt knows a lot about space … like how we feel connected to the stars because we are all made of stardust. And that Mum’s new boyfriend, Galactic Gavin, has eyes that twinkle like Sirius, the brightest star in the night sky. And that sometimes the perfect place for her sister, Terrible Topaz, would be a black hole. But Mabel doesn’t know how to fill the space in her heart that Dad left when he walked out. And so she sets out on a mission of discovery.