Is Tom Cruise Mormon?
No. Tom Cruise is well known to be a Scientologist.
No. Not now; not ever. Tom Cruise is most associated with the practice of Scientology. Those who practice Scientology believe that humans are immortal and have simply forgotten their nature. Mormons and Scientologists share that belief, and that belief alone. There's nothing else about the two faiths that is comparable. As a point of reference, Mormons are devout Christians; Scientologists have no interest at all in Christianity.