There is currently not a synopsis for this book

goodreads summary

Biggles investigates the kidnapping of some highly specialised scientists. The book features Algy, Ginger and Bertie although Algy only plays a very small part in the story. A bizarre clue, involving three V's tattooed on a Chinaman's head, leads the team to a remote part of China. A rescue mission is mounted and this includes Chinese expert and speaker, Captain Roderick Mayne. The team locate the villains' base and have to organise the escape of the captured scientists. Biggles and Ginger infiltrate their camp and discover the presence of an old enemy.