Call first just to get to know more about me and get some context for my CV. Maybe 20 minutes and the guy I spoke to was really nice and sounds genuine. Then I went in for an interview in person to the site. They were all really friendly and I met we the same guy I spoke to on the phone (he was in HR) and then the head of the department I was applying for. I can't remember the questions they were asking but a lot of it situational questions. They made a big point of being honest and open. After the interview they called me shortly after (can't remember if it was the day or the day after), to arrange me coming in for a a few hours of shadowing the team. When I got there I got shown around the building(s) and then got to meet the team and who I'd be shadowing. They were all really friendly and encouraged questions saying stuff like "if you get the job we expect you to ask loads of questions and that absolutely fine and good". After it was up, they said they'd call soon after. They called on the Monday (I had the shadowing on the Friday before) and said that I got the job.