Well, I deal with that all the time. I am a perpetual outsider.
Generally there are several people like that every place I go. Plus those that resent me for my fees, independence, etc.
After a few days of being very passive and quiet, gathering information, helping where I can, I have usually identified those that are such roadblocks to success. I either confront them privately one on one, explaining my role as being there to help them accomplish the task, and not to demean or belittle anyone, or I have them moved to a role that will not obstruct success of the project. I have found through years of experience that while my technical knowledge is a key skill to bring to a job, it is usually my ability to identify and neutralize "people problems" that are ultimately what bring a project to success.
There have been several projects where the key person was the problem... The task there is to organize the support team such that they can tolerate and even facilitate the success of the problem person and therefore the entire project.
The important principle is to keep the overarching goal of the team in mind, and organize the team to accomplish that goal. Sometimes is means the arrogance has to go, and sometimes it means the arrogance has to be catered to.
Just be real about what it is you want to do, and find the best way to do it. You don't have to destroy a barrier, you just need to get past it. I do my damnedest to save someone from the hatchet but if after explaining how its going to be, they sometimes throw themselves upon the blade neck first. Usually that's someone who cannot come to grips with their unimportance.