If there’s one thing sci-fi movies have taught us over the year it’s that combining one animal with another animal almost always ends badly. Scientists in China aren’t trying to create mutant monsters, but they did successfully create baby pigs with monkey cells. Yes, you read that correctly.

As NewScientist reports, a team of researchers from the State Key Laboratory of Stem Cell and Reproductive Biology in Beijing set about creating the first pig-monkey chimeras. A chimera is any organism that includes living cells of different genotypes. Put simply, the researchers added monkey cells to pig embryos, allowed mature female pigs to carry those embryos to term and then observed the resulting piglets.

The team worked with over 4,000 embryos, all of which were implanted in sows. Of those thousands of embryos, just ten of them resulted in a pregnancy that was carried to full term. The appearance of the piglets remained largely unchanged, but the scientists were able to observe the monkey cells, which were modified to fluoresce for easy visibility. Of the ten piglets, only two of them were actually chimeras. Both of the piglets died within one week of being born. Their cause of death has not been determined.

This might all sound pretty grim and, to be honest, a bit creepy, but the goal of the research is actually rather interesting. The scientists are working towards the ability to grow human organs in pigs. The idea is that, with organ transplant waitlists claiming lives around the globe, ready-to-use human organs grown in pigs could offer a solution.

Saving human lives is a great thing, of course, but raising pigs stuffed with human guts only to kill them and harvest their innards raises some pretty serious ethical concerns. Nevertheless, the work continues and while the deaths of the two piglets (and the low success rate in creating the chimeras) is a setback, this isn’t likely to be the last we hear of the project.