For me, the mission 'Uncle Vlad' is very interesting. It has a great story - line that is full of drama and tension. You are dealing with family - like relationships within the criminal underworld of Liberty City. Also, some of the side missions can be really engaging. They offer a break from the main story but still tie in well with the overall atmosphere of the game. For example, some side missions might involve helping out a local business owner by dealing with some thugs, which gives you a different perspective on the game world.