There is a test that needs to be passed before the interview actually starts. Relatively simple that is basic bookkeeping. Then you go into the interview with who would normally be your team. If you pass you will be invited back for a second round interview with more senior members.

I have interviewed twice within 2 weeks. The first round interview is 2:1 and the second round is 1:1 with the senior manager. There is a simple bookkeeping question in the second interview.