Among Quinn's things, Casey finds a device which she accidentally activates.  At first, she notices nothing unusual.  That is, until she realizes that she can pass through walls.  This presents a problem when she tries to turn off the device and it passes through her fingers.  Filled with panic, she goes to find Tristan, hoping he can deactivate the Niflheim technology before Quinn finds out.  Unfortunately, Tristan is unable to see Casey and, when she screams, he doesn't seem to hear her either.  Frightened, Casey next attempts to solicit help from Aden, Adriana, and finally, her father, Hunter.  No one can see or hear her.

 

Desperate, Casey turns, at last, to Lex.  Because of Lex's strange ability to see through walls, she is able to see and hear Casey, as is Tugs.  They agree to help Casey.  Tugs begins to work with his technology while Lex takes Casey to the library.  In the library, Lex and Casey snipe at each other a bit, earning Lex some very dirty looks.  Their fighting ends abruptly when a member of the Ra Family appears.  She is also able to see Casey and, under orders from the matron Sara, kidnaps the two women.  Just as she is leaving, Quinn appears and realizes that Casey must be invisible.  He quickly turns to Tugs.  The two of them resolve to rescue the women.

 

In order to evade detection by the Ra Family, Quinn realizes he must get rid of his powers, which act as a flare in the presence of the Ra Family members.  He and Tugs travel to a sorceress who saps away Quinn's powers and sends the boys to the Ra Pyramid.  Using nothing but technology, they manage to break in and avoid the guards.  Along the way, they pass a room filled with treasure and Quinn swipes a helmet made of lapis.  Meanwhile, locked in the cell and under threat of death for Lex, Casey and Lex slowly reconcile, each one apologizing and forgiving in turn.

 

Tugs and Quinn break into the cell to free the girls, but Sara appears, threatening to kill Lex.  She refuses to give up the girls.  Quinn, however, pulls out the lapis helmet and threatens to destroy it.  Desperate to keep the artifact, Sara agrees to let them go.  She warns Quinn and Casey, however, that this is not the end.  Since Casey is part Ra, and since she was improperly carved by Hesiod, a part of her will always belong to the Ra Family.  The group escapes.  Quinn has his powers restored.  With fences mended, Lex and Casey decide to continue their travels together.