S & S in the Wizarding World

an unexpected letter from you-know-who changes the whole life of Mr. Rickard Ambrose and Lily Linton when they are magically transported to a place where buttons could talk, wands are used to fight instead of guns, there are frogs of every flavor to eat and most importantly a communication system better than pneumatic tube : the floo powder.
But amidst all this a danger lurks in the corner.