I loved this - the secret identity, Pen's predictaments, even her disability, which I thought was handled really well. This was so unique in that I have never read a mystery with a protagonist who was in a wheelchair.
That alone is enough to make this unique, but the story itself was fantastic. I loved the ending, there was so much going on, and it all fell together so well. I did not guess what was going to happen right up until the very end. And it was very satisfying.
I felt this did something that few mysteries manage to do well, which was handle a large cast of characters and develop them well. The corporate men and the male law enforcement characters were easy to confuse, but once I got clear who was who, I was able to keep them apart. There were a couple of great women characters in this story, which as we know can be difficult to come by in mysteries.
I loved the corporate espionage angle of this and I'd love to find the earlier Pen Wilkinson books and have a go at them.