Jeanmarie Troxell and Malcolm Soo are both bossy， both latchkey children， and both want to be famous. It is Tallulah， the aged -- and somewhat dead -- actress they meet under the small hill they have called Jericho Tel， who tells them that it takes three things to make a star. It is also Tallulah who sends them into a state of invisibility and on an errand. They are to find the necklace containing the famous Regina Stone， which someone took from around her neck just after she died and just before her soul left her body. While they are invisible， Malcolm and Jeanmarie meet some street performers who were friends of Tallulah s and who were present when she died. There is Nicolai Ion Simonescu， the ventriloquist who was in love with Emmagene Krebs， the sweet young folk singer who had eighteen thousand songs to sing. Did Nicolai take the necklace to bankroll his successful puppet business? Or did Patrick Henry Mermelstein， the truly klutzy magician， who now has a profitable record shop? Or did the butler do it? Before they find The Regina Stone， Malcolm and Jeanmarie learn two of the three things it takes to make a star. But the secret of the third ingredient of stardom is hidden with the secret of The Regina Stone. And before they can find both， Malcolm and Jeanmarie must have courage enough to make their invisible selves visible.