Case 48 hours in advance. Take significant time to prep, you can generally guess what the case question will be. I would recommend prepping the agenda and slides for the presentation in advance.
I applied through college or university. The process took 2 weeks. I interviewed at PwC (McLean, VA) in Oct 2013
Interview
Selected for an on-campus interview and was invited to a meet and greet event the night before. There were a bunch of PwC employees there and we all mingled and ate, it was very laid back. The next day was my 1 on 1 interview with a manager, which was very relaxed. We basically had a conversation for an our, and I didn't feel like I was being grilled at all. I heard back a few days later with an invite to the on-site visit that Friday in McLean. Myself and about 15 other candidates were there. We met in the lobby, got a presentation with lunch, and then the interviews began. My first interview was with a manager and that consisted of a few behavioral questions. My second interview was with a partner and it was again behavioral. My last interview was with another manager, and this was the case interview. They gave us the case in advance but gave us the questions that day. The case was pretty complicated and the questions were specific to each candidate's line of service. This is the first time PwC is doing case studies for undergrad interns. Prepare well in advance and you will wow them.
Interview questions [1]
Question 1
Tell me about a time an acquaintance helped you complete a task or learn something new.
Why PwC?
What are you looking for in an internship?