He had seen no door that would have served as secret entrance.

Human beings would now know where to look for the secret entrance.

Otherwise, he would use the secret entrance as a matter of course.

I went in by the secret entrance that led into the basement.

We've been down here for hours and we still haven't found this secret entrance of yours.

"Can you tell us how to find the secret entrance into the underground?"

The secret entrance came from a house across the street.

The Shadow had come through the secret entrance from the house across the street.

That meant I had to have some sort of secret entrance.

There must be some secret entrance in the temple itself.