The initial phone interview was short and simple. I explained a sample question and talked about what I liked about the LSAT. It was later revealed to me that this step is mostly to ensure that you have a minimum level of social competence.
I was invited to their infamous training in LA. TM frames this as a training and not an extended interview, since according to them there is work available for everyone invited and they must cancel classes when candidates do not make it through training. Regardless of how it is framed, many candidates do not make it through this stage. Only about half of my cohort made it through the week.
The week is spent learning their curriculum, teaching LSAT questions, and prepping for teaching. Questions are taught to a group that includes both real LSAT students and actors who don't know anything about the test. You are evaluated on your teaching, and throughout the week candidates who are deemed inadequate will disappear from training without any explanation. The whole process is exhausting as you are learning, teaching, or prepping your sample lessons for 12+ hours a day, without any certainty that you will make it through to the end.
They throw you a nice open bar party at the end if you make it.