While expanding her mind-view, Carmen Willathorpe sensed an intense concentration of consciousness as a point of light thousands of light-years from where she was sitting on a planet the Lorengi called Stone. Carmen, the Lorengi leader, Ahleeto and the sentient Lorengi ship, Thelika, are joined by other Sunaj scientists as they race to investigate the incredible light and find a large spherical object behind a translucent barrier. The barrier appears to be a kind of window that may be providing a view into another dimension. Finding alien designed ships are also behind the barrier, they try to find out if there are conscious beings inside the ships. They are unable to contact them. How would they get to them if they are there? Are they still alive? Do they need to be rescued? Why does it seem like nothing behind the barrier is moving? If a rescue is needed, and they find their way in, will Carmen and her crew be able to find their way back out? Or will they be trapped inside an unknown dimension forever? Finding the answers to these questions will set the scientists on a journey that is more than they ever imagined, and raise speculations about humanity's role in the universe.