I was reading this book recently and I had an idea for a plot twist that I'd like to RP out. I'm willing to make changes based on your ideas. But for now the plot would go like this:

Carrigan is a King's Messenger ("Green Rider" in the book) and wears a winged horse brooch. It has a magical concealment spell. She and her message pose a threat to a deposed king and he has her captured and brought to him by two elite swordsman--the last of his personal guard. They bring her across the country claiming to be bounty hunters and telling wild lies about her to turn everyone they meet against her. But the stories get more and more unbelievable and one day they meet a man who sees through them but pretends not to. This is helped along by the fact that he can see through the brooch's concealment spell. Perhaps he is a messenger too or WAS at one time--either was rejected eventually or failed to pass his training stage or is simply retired or is the son of a messenger and has some magical ability--enough to see through the concealment spell but not enough to be accepted into the ranks.

There was no such person in the actual book. She had a little help here and there and got away on her own. But I think it would be very interesting to write a version where she is saved by someone. The King's Messengers have special horses. If he is a retired one he could have a horse like hers and they could travel together on equal footing. Or perhaps her horse was sold or injured or even killed? That would give them a better reason to stick together.

Carrigan is a great character so I don't feel the need to come up with another one. I'll be tweaking aspects of her though since she was so frustrating to me in that series.