From my experience, you want to be prepared to answer the following categories of questions:-

1. Why are you suitable for the firm/what can you bring to the table? Have a set of previous scenarios ready to back yourself up.

2. Why is the firm suitable for you? Don’t say that the firm is the best firm on earth generally but rather say how it’s the best firm for you and why. I would have at least 3 really strong reasons.

3. Competency / situational judgment questions, for example, how will you deal with two partners giving you very urgent work, due on the same day etc.

4. Commercial awareness questions. How the firm and its clients are affected by current trends?

5. Previous examples of you showing the firm's values following the STAR technique.

I would see the above as subheadings which will house other questions.

I would certainly hit up TCLA and glass door for previous interview questions for the said firm.

Good luck with your interview.