SOLVED. Woman has 4 identities, incl. Petra, Stephanie. Uses asthma inhaler to get drugs/explosive(?) onto a plane? [s]

[Evander]

I think the title had the word "Breathing" in it, but perhaps I'm getting mixed up.

The protagonist was a woman, I believe a sex worker, who is contacted by someone to bust a terrorist. The book is split into four, one for each of her identities. I remember two names, Petra and Stephanie. I believe it dealt with a Muslim terrorist, that one of her identities was sent to an army camp, and that she managed to sneak some substance onto a plane using an asthma inhaler.

Any information would be great. I read this book quite young and gave away my copy, so I can't remember the author details, etc.

EDIT: I probably read this in the early 2000s, and I believe the cover was purple or blue.

[Kris]

The Rhythm Section by Mark Burnell seems to match your description.

[Evander]

That's the one! Thank you so much! I was getting the name mixed up with Stephen King's "The Breathing Method", I think.

[Kris]

You're welcome. :)