The relationship between Mac and Irina

I have always wondered about their relationship. In the warehouse Irina says to Mac in the truck, "Good job." But Irina didn't seem to care when Mac betrayed her. And she ignored Mac in the temple. So I'm hoping someone can explain all this to me.

Without going into detail here, James Rollins' adaptation of the movie has a lot more interaction between Mac and Spalko. I'd recommend it - I really enjoyed it, and it explained some of the rather more mystifying aspects of the film.