I already interned at Accenture prior to receiving this offer, so the process was slightly different for me. Given that I interned in SI&T but wanted to get into MCIM, i went through a number of interviews with various members of the MCIM team.
I had an interview with a Senior Mgr from the F&PM team which was a roughly 60 minute interview aimed at a bit of technical competency as well as mainly getting to know you type questions, followed by a catch up with a Senior Executive, which was mainly a getting to know you interview.
If you came straight through off the street, you would have a phone interview (10 mins) followed by possibly an interview with HR or a Manager before getting to the above stage