That depends on what they're looking for in captives, really. It would be a simple enough spell, if it had the proper direction.

[He rolls his shoulder in a shrug. Only the Sphere knows what it's original purpose was, and it seems to have conveniently forgotten.]

No. [He smiles, though.] This is but one very small pond in the vast ocean of reality. I could show you, but...maybe later. When you're ready.