In the very first episode of Westworld, Abernathy, one of the robotic hosts, finds an old photo of a woman in a modern city. He is puzzled by it and shows it to his daughter, Dolores. Dolores looks at it and replies, "It doesn't look like anything to me," the standard response the hosts are programmed to give when confronted by anything that falls outside their narratives. (The fact that Abernathy didn't have that response is telling.) The next morning Dolores finds her father still sitting on the front porch of the house staring at the photo, ending with him having a total breakdown.

It turns out the photo was a stock image from Getty:

The woman in the photo was supposedly the character William's fiancee outside the park. Proving that the creators of Westworld pay attention to every detail, they apparently tracked down the model in the Getty photo and she made a cameo in the most recent episode:

Every detail is important in this series. Just sayin'…