The film's most prominent concerns greet us as we begin to watch—the classic twinned themes of boobs and sleep.
Valerie Leon is really pretty and also pretty effective as both Margaret, an Egyptologist's daughter, and Tera, ancient Egyptian queen who also sleeps shamelessly.
You can tell them apart because Tera's hand was hacked off and fed to very famished jackals in the stirring scene below.
Then we jet forward into more modern times and Margaret spends some time with her boyfriend, Tod Browning (bold name choice, movie). Her father spends most of his time in bed, fulfilling the film's somnolence quota. Meanwhile, one of dad's colleagues, Corbeck (a spirited James Villiers), is plotting to resurrect Tera to satisfy his Nietzschean ideals.
This is based on a non-Dracula Bram Stoker story, which might explain its simultaneous overcomplexity and paucity of actual content. The movie, like Valerie Leon herself, is all about the build, so viewers beware—this Mummy moves more slowly than most of its kind.
But, if you're indulgent, there are benefits to watching. Hammer hired actresses of a certain type, but they also never hired actresses who were incompetent and Leon acquits herself well in her dual role. I enjoyed some of the wittier touches, like post-possession Margaret's kohl makeup and the very final scene that compensates for a less-effective last third. So yeah.