Four x 30 minute interviews in STAR (Situation, Task Action, Result) format. It was pretty taxing as you're meeting four completely different people but the upside of it is that your interview is all completed in the one day rather than having to come back for a second round. Questions are all taken from a standard list that they have, it's generally one HR person and three technical and I think you need to score an average of 4/5 from the four interviewers to be offered a job