I don't think I'll have a problem staying natural. However, it becomes quickly apparent that all these big shots are fucked up in the head some way or another, so staying on the same page as them is an eruption of Mt. Awkward, and you're running down a hill that twitches and refers to ex wives as values on a scale of 10.
Everyone's fucked in the head. That's normal. They just have less fear about hiding that fear bc they're successful. I've heard exec from huge brands speak as you would expect a racist entitled 17 year old. I've also had a lively debate regarding game of thrones with their bosses. Find that common ground and if you have nothing to say on a subject, just nod and smile and when the conversation lulls ask them how they got into this field of work or what they do for fun or whatever.