Listening to the Librivox audiobook of this, which is pretty well done.

The politics in this is really slimy (Orczy is very pro-nobility and reacting against the French Revolution by upping her disdain for the poor), but they are entertaining adventure novels if you roll your eyes at all that. This is not me advocating ignoring it - think it's important to pay attention and read mindfully when it comes to that kind of thing - never ignore it.