I’m willing to have a fair suspension of disbelief when it comes to steampunkish science fiction. The alien weapon fitting a human perfectly? Fine. The convenient amnesia that allows exposition to be on its on time? Fine. But there are limits.
For example, “gold is just as rare to them as it is to you.” Really? Is the Earth somehow so extra-ordinarily special in terms of gold, that they would come here, where an intelligent species on the verge of discovering space technology really likes it gold, instead of trying anything else not so involved? For example, mining for gold on any other planet in the solar system? (I’m not going to even mention solutions like surrounding a nuclear reactor with lead, and using a centrifuge to separate out gold from lead).
But I’m not going to just complain. I’m going to show what it should have been — what alternate premise could have made the movie make sense!
On an alien planet, there lived two intelligent species, from completely parallel evolutionary lines. Where we evolved a sense of humor as a signal of intelligence, one of them, species R, developed a sense of taste — for intelligent species. The R males would find a member of the other intelligent species, trap it, and present it to the female as part of their mating ritual, very early on in their evolution. Eventually, they would be herding the other species, P, and would develop complete disgust for “meat that doesn’t talk”. For the Rs, eating a meal that doesn’t talk is a way of subsistence on sub-par food — like eating worms for us, a way to survive in the wild while reaching civilization, not a part of their diet.
In fact, they begun to be connesuirs of intelligent species meat. They fly around the galaxy, find interesting intelligences, and eat them. As soon as they detect signs of intelligence, they swoop in and start munching about. For Earth, that meant playing around with electricity, and early radio waves, was the first sign. Soon after some of the early experiments in 1872, the vast probe system they laid out informed them that Earth had intelligent life. Squishy, soft and tiny, those intelligences were unlikely to prove a threat. But how could they get the amount of food they needed?
Enter the gold. Where gold is found, the humans go, the aliens discover. They started stealing the western gold not because they liked it, but because they knew it would get the humans to them — and into their ships, where they could be packaged and kept for a while. They had to experiment with preparation, and an unfortunate number of people were burned to a crisp from culinary experiments gone wrong.
Ella’s species, of course, was lured in with the same trick — stealing their gold to get the people. She has never, and sadly will never, discover it was all a ploy for the aliens previous planet-wide feast.