Mamie Pocock Timeline and Summary

Mamie shows up in Paris with Sarah and Jim. We've heard a lot about her, but up until now, she has always sounded like a pretty face who's supposed to lure Chad back to Woollett but doesn't have too much going on aside from that.
When we meet Mamie, it's clear she has a mind of her own. She hangs out with Chad a little, but it becomes obvious that there's no romance between them.
Later, we learn that Mamie isn't really interested in Chad anymore. She wanted to be the woman who "saved" him by turning him into a good man. But she can see that this job has already been done by Madame de Vionnet.
While in Paris, Mamie forms a relationship with the artist Bilham. When Mamie leaves Paris with Sarah and Jim, Bilham goes with her.
It looks like the two might be on the path to the only successful relationship in the book.