SOLVED. Children take underground train to the Arctic to stop evil geneticists. [s]

[David]

Hi,
I got a book from the local library 5-10 years ago.
It is a children/middle grade level chapter book.
The copy I read had a blue cover with a red wind-driven snow-sled of some sort on it, IIRC.
The book is about two children, siblings, who enter an underground train system by using a passphrase in a shoe store.
They ride the train to one of the poles, I believe the North one. There they encounter evil geneticist(s) who have kidnapped their father. The geneticists are about to perform some kind of altering operation on a girl.

[Kris]

The 7 Professors of the Far North by John Fardell seems to match your description.

Some Goodreads reviewers say: "...the evil Professor Murdo is out to kill the rest of the original "7 Professors of the Far North"--a group of brilliant scientists who were once going to teach at a university on Nordbergen, an island in the Arctic Circle...Murdo's henchmen arrive and kidnap the professors..." | "I was fascinating about travelling on wonderful machines like the secretious underground trains." | "...one of the seven (Professor Roderick Murdo) turned out to have evil plans regarding the human race...experimenting on..."

It sounds like the kids' uncle was kidnapped.

[David]

That's it! Thanks for your help!

[Kris]

You're welcome! Glad you found your book. It sounds like a fun read.