Help! Movie/Show with a Shimmery Alien

I’m not sure if it was a movie or an episode of a tv show, but essentially there was an alien/lifeform that was sort of a shimmery, rainbow color and resembled a flat sea creature (think stingray) that was wavy and had lights on the edges. I feel someone tried to communicate with it and maybe had to leave with it? Maybe. Anyways, any help would be appreciated!