"dateline." members of the military risk their lives every day. but a high-ranking army officer was dead in her own home and not killed by an enemy of the u.s., but by someone she knew and trusted. here's andrea canning with "deadly devotion." >> reporter: in the hot and dangerous middle east, she held her own in the company of men. a captain and a commander whose devotion never wavered. >> she inspired people. and that's maybe why she made such a great commander. she inspired her troops. she inspired those that worked for her to want to do well. >> reporter: she was captain lynn armstrong reister. army veteran debbie moore was one of her best friends. >> lynn was very intelligent. she knew how to bring out the best in people. i just loved her. she was someone to be inspired by. she inspired people. >> reporter: she had a big role in the military. >> very big role, yeah.