Rachel and Kirsty and their families meet on the ferry, on the way to Rainspell Island for a holiday. The girls are sure they'll have lots of adventures together, especially as Rainspell Island seems almost magical. But when they go on a hunt, the first day, for the end of a rainbow neither of them really expects for find a pot at the end of it. Especially not one with a ruby red fairy trapped inside! And so begin Rachel and Kirsty's adventure to find the seven Rainbow Fairies, banished by the evil Jack Frost, and restore colour to Fairyland.
This is book 7 from the series.