Filled in very lengthy online application form and did online tests. Invited to onsite interview in headquarters in Enfield. Was in a group of 6 people and started with an employee giving a presentation lasting around 30 minutes. The assessments started with an IQ test with around 40 minutes to complete - I completed around 60% of the questions before running out of time. We then had 2 subsequent questions consisting of a problem statement and various questions most of which being open-ended, suggest a method for ... etc. The first question was basically about passing messages around a network, efficiency, how to know for sure receiver has received the message. The second was about coding a computer to play a variant of blackjack and what approach/algorithm to use. The whole game tree is too large to evaluate but you can use probabilistic methods to guarantee optimality at each turn. The interviews were rather mundane, though the interviewers were very friendly. The first interview involved discussing the test and a few extension questions which were relatively straightforward. In the second interview they presented a variant to the blackjack problem which was basically the same but with different values for payoffs. Overall the experience was mixed, the onsite IQ test was a little out of place, the questions were relatively interesting but the interview discussions and questions were not.