This is a brilliant short book with a lot packed in. It takes place in the future, after an algal bloom created fumes (the Reek) which made the air toxic. At first it was ignored, as only birds were affected, but it rapidly grew until the whole planet was suffering. An internet billionaire, Axel Brodie, came up with a way to purify the air which allowed the human race to survive. Clean air is purchased from his company, Zephyr, a huge conglomerate which now pretty much controls everything: security, transport, housing and education as well as access to the air needed to breathe.
Surep (who likes to go by Sparrow) had to leave school at the age of 12 after not getting the results needed to continue her education. Since then, she has been working long hours as a courier to earn enough credits for her family to survive. Her younger sister is still at school and her only other family is her grandad who isn't fit enough to work. They live in a two room apartment with leaky seals which allow the Reek in and they often wake up coughing. Both Sparrow and her grandad eke out the treated air as much as they can to save enough credits for food and rent.
A brightness amongst the gloom of their situation is the way Sparrow carries out her job. She uses skates to get around but they are hover skates. She also has a magnetic tether which allows her to swing around the place like Spiderman. There are some thrilling scenes of her in action with these as she takes risks to make the deliveries on time. She can't afford to get a bad review and not be paid.
The tether was made by Sparrow's friend, Miriam, an old lady who lives in a junkyard. She invents a new way to purify the air and this leads to someone trying to silence her. She tasks Sparrow with making a delivery to Axel Brodie and it will be the most difficult Sparrow has ever made.
I particularly enjoyed that the story is set in Edinburgh, a real-life place. It definitely made it seem more like it was something that could be taking place in our near future rather than being a far off possibility. I also liked the intergenerational friendship between Sparrow and Miriam.
As well as looking at what might happen to the world because of climate change the book touches on several other issues. There's the huge conglomerate controlling everything. A rigged system where only the wealthy have any chance of a decent life. Friends becoming divided because of their different situations. The difficulties of working as a courier when so much weight is given to your rating. Corrupt law enforcement. The book is only a bit over 100 pages so there isn't the opportunity to go into any of it indepth but it's there and has the potential to get readers thinking.
It's printed in a dyslexic-friendly format and I think it will most appeal to readers aged 9-11. Older or more experienced readers may find it a little simplistic but it's still exciting. It could also be good for weak readers aged 11-13.