Magic in the '50s

It's impossible to pick one genre description for The Apothecary by Maile Meloy.  The story includes bits of historical fiction, adventure, mystery, and even fantasy, which makes for an interesting (but sometimes confusing) read.  The time is 1952, and Janie and her family have just moved from the U.S. to London.  Janie becomes friends with Benjamin Burrows, whose father is an apothecary (a British term for pharmacist).  After Benjamin's father is apparently kidnapped, the two friends are not only left with a 700-year-old book of magic potions. but they learn that Mr. Burrows is actually part of an international group of scientists that are trying to contain the destructive power of a bomb being developed by the Soviets.  They also contend with a mysterious garden, a teacher who may be a double agent, and Pip, a friendly and mischievous pickpocket.  If you prefer a logical and consistent plot, you may want to pass this one up, but if you enjoy adventure, check it out.