The Island Of Adventure (Adventure #1) by Enid Blyton

Format : Paperback 

Condition : New but minor dirty , dent

Genre : Children

For Philip, Dinah, Lucy-Ann and Jack, the holiday in Cornwall is everything they'd hoped for - until they begin to realise that something very sinister is taking place on the mysterious Isle of Gloom. But they're not prepared for the adventure that awaits them in the abandoned copper mines and secret tunnels beneath the sea.