I applied through my college's job platform, Handshake, and got a first round. The first round consisted of two, 30 minute interviews. The first 5 minutes or so was a brief introduction (name, their position, "why did you apply?"), followed by a case. The cases themselves were somewhat math heavy, so be prepared. Both were multitiered, getting to one "conclusions" then considering a complication (so more math). Overall the interviewers were very helpful during the process and answered questions in a helpful manner. In between my first and final rounds (there are only two) I ran a practice case with my interview "buddy" that reached out via email. It was super helpful and informal, and the feedback I got was valuable; definitely try to do one with your buddy (or even two, mine offered!). The final round was at their office (Arlington for me) from 8:00AM to 3:15PM. There was a panel, presentation, and four, 45 minute long interviews. These were similar to the 30 minutes interviews, except with more time for questions and behavioral stuff before and after the case. The cases were math heavy, again, but varied on topics and focus. Different industry each time, but sometimes the math seemed to be the most important part, other times the logic and strategy of your decisions. Either way both were important, the emphasis just changed. For one I had to sketch graphs and interpret them, for example. It took them the weekend to get back to me.

Skype interview followed by final round super day. The final round was in Arlington with breakfast, then a presentation about the firm, then 4x45 minute interviews with a 90 minute lunch break at some point.