HOW FAR WOULD YOU GO TO HELP A FRIEND? Mischievous sisters Diane and Robin are already in trouble with their father, Captain William Marsh, commander of the starship Polaris, for a stunt they just pulled. Their punishment (grounded...again!) is cut short with the arrival of Jannel, a soft-spoken, shy girl roughly their age, and the future ruler of the planet Lasusia. Jannel has been sent to the Polaris for safekeeping from a deadly virus running rampant on her home world. As Diane and Robin learn about their new friend and the problems she faces on her war-torn planet, they vow to help her, even though they understand it means getting deeper into trouble with their father. But they are soon in over their heads, stricken by the virus, and trapped by their father's mortal enemy. They must use all their instincts and resources to escape before they perish from the virus, along with all hopes of planetary peace.