One of the earliest cinematic depictions of the Conclave, this 1952 forgotten movie about Pope Pius X is also one of the only depictions of Pius X. While the first half of this movie is boring, the second half remains relevant with the death of Pope Leo and the process of the conclave in the Sistine Chapel. The title is very deceiving if not just a downright lie. False advertising at its best, there was not a "secret" conclave in 1914 not does this movie attempt to say that there was. I do question that this was ever the American title when it debuted in the 1950s.
Either way, it is an interesting take on the life and end of Pope Pius X. If you need to watch every movie about every Pope ever made, than this is on your list.