The setting is Britain.
There's a murder on the train the twins are traveling on, and there's a mysterious man following the twins and Muzz, who goes to France on what the twins suspect is blackmail.
And the Great Mogul Diamond disappears.
Who is the mysterious man?
Who is blackmailing Muzz?
Who is the thief who is trying to frame Muzz Elliot?
And what Christian principles will the twins learn?
And of course they want to find their mother.
This series is mysterious and interesting, following abandoned twins who get adopted (but who always long for their mother) and then have adventures relating to their adopted parents. Although this takes place in modern times, the feel of the book makes it seem in the past. And the fact it's a graphic novel series (and did not originate as a longer series) makes it even more original and creative.
I really enjoyed reading this book.
It deserves a 10.
Praying you have faith, hope, and love always,