There is currently not a synopsis for this book

goodreads summary

Biggles and his friends are given a seemingly impossible task when they are asked to locate the luxury yacht, Cordelia, and its master. The five-hundred-ton vessel - owned by troubled international financier Otto Brandt - simply slipped her mooring one night and sailed off into obscurity on the high seas. The team's mission is further complicated by a young Italian who is bent on revenge.