There are two rounds of interviews, the final one is with the Managing Partner. There's usually an aptitude test as well. The aptitude test consist of things you have read in Uni, so go through some of the basic topics

The process was quite long and the interviews went on to late hours, however in spite of the rigorous interview the questions asked suited the role advertised for. All in all, the time taken to conduct the interviews should be similar to the working hours