Disclosure Day, Steven Spielberg’s latest sci-fi thriller, concludes with an alien delivering a mysterious message that the film intentionally withholds from viewers.

In “Disclosure Day,” out Friday, Steven Spielberg is once again inviting audiences to ponder the existence of extraterrestrial life — and the implications it would have for religion on Earth.

We follow Daniel Kellner (Josh O'Connor), a cybersecurity specialist who has defected from the "baddies", and Margaret Fairchild (Emily Blunt), a TV weather reporter who unwittingly becomes host to al...