There are 3 levels: HR, Senior Manager, and Partner interviews.
HR rightly or wrongly are more an "in-the-box"; make sure you customize resume according to the published job descriptions. Interviews with these are quite standard: grades, non-curricular activities, willingness to work long hours.
Senior Manager interviews (if you get to here) will talk more on the details of the job and usual projects. These are more technical in nature.
Partner interviews are usually brief; just a look-see on how you would fit and what your career prospects are.