Cardinal Lawrence is tasked with leading one of the world's most secretive and ancient events, selecting a new Pope. Once the Catholic Church’s most powerful leaders have gathered from around the world and are locked together in the Vatican halls, Lawrence finds himself at the center of a conspiracy and discovers a secret that could shake the very foundation of The Church.
There are no acutely claustrophobic situations (people trapped in narrow spaces, etc.) but the general situation can be claustrophobic in a broader way: The characters spend most of the movie stuck inside a building that they're not allowed to leave or interact with the outside world or even look out the windows.