Lorelei (2021)

World War I - After an intense air battle British pilot James Mannock crash lands into the Ocean only to be saved by the mysterious nymph Lorelei, or so he thinks. Pulled between two realities, in one he spends his days by the rockpool with Lorelei and in the alternate he is locked in an underground mental hospital. The question is, which one is real? Is Lorelei a desperate escape into the world of his imagination or is she a memory that no one but James will believe ever happened?