I remember reading (maybe half a decade ago) a short story in an anthology featuring time travel.
The story followed a group of scientists sending a drone to the future and watching the video of the future afterwards. They started getting puzzled as each time they sent the drone, it returned with a video of worse future.
In the future they start seeing hordes of "alien" creatures that kill every trace of humanity. One of the scientists eventually decides to go himself, and when he comes back to the present, he has one of the creature with him.