Welcome to the community! Sorry I'm so late in replying!I think, this early in the series, the reader doesn't KNOW Lymond well enough to recognize him as Christian's prisoner. Especially when we haven't seen him act so charming and open before. So I think it's vague who the prisoner is, purposefully, and an easy deceit. Has your friend read the series before? Reading it now, I think "Of COURSE it's Lymond!" but that's only because I know him so well this time around.