The Twilight Zone is a dimension of sight and sound. People who reach it quickly find it is not a dimension of color, though. It can be accessed quite easily through its front door, then breaking through a window as your own visitors normally do.
The Twilight Zone is ancient but has nothing to do with vampires. Even if it was, being a place without color, you couldn't tell if there was blood or not. It is populated with beings that look remarkably like people on Earth, today. However, it is clear that they are not from here. For example, Robert Redford appears to live in the Twilight Zone, but looks nothing like the 1000-year-old man we know. Similarly, a William Shatner lookalike is in the Zone, but with his/her/its stilted, fake one-dimensional emotionalism and bad toupee, he/she/it is certainly not the distinguished gentleman found on Earth.