As they passed him, heading for the laboratory door, it opened.

Nothing stopped her as she cleared the laboratory door and ran for freedom.

His hand was hidden from view behind him as he stood beside the laboratory door.

The big engineer had left his post at the laboratory door, was rushing toward the back.

The technician put his head out of the laboratory door.

And who else could come in by the laboratory door from the street?

Neither man heard the tiny click that came from the laboratory door.

He turned away from them and strode toward the laboratory door.

Only then did he look up at the slender man who stood inside the laboratory door.

Someone had stopped in front of his laboratory door.