Firstly, it would start with an online test then they judge you on your cognitive ability with an UCAT test and then they will start scheduling technical interviews 1,2,3,4 levels and more until they can reject you.
At the final director level interview, they would have 2-3 Sr.SDET's and one HR and they say they have them because they want to assess them and not you. Great way of interviewing a candidate. The rounds lasts for 2hrs apprx and would eat up all your stamina and then they say you failed at technical answering. Such a nice trap!! They will never get back to you with a feedback once rejected and the consultancy who sets up all this will scare you at every level mentioning they are so and so and please be accurate and etc...