The Rainbow Ghost Bus — Sue Perkins

Jack and his family move into a renovated Victorian bus depot. One night a ghost of the number thirteen bus arrives on their patio. It takes Jack and his older sister Kate to a land of sunshine and rainbows where they must search for the missing letters of the words The Rainbow Bus Company as shown on the company logo.

The ghost bus visits many times, each time transporting them to a different land to search for the letters they need to free the bus and solve the mystery surrounding the missing owners of the company.

The danger they encounter in the countries of Sunland, Fireland, Cloudland and Snowland force them to work as a team to solve each mystery. The bus leaves them in each country, and will not return to collect them until they have found the hidden letters.