Doors of Destiny

Alternate timelines and moral lessons

When their grandad, Professor Thomas Shakleman, brilliant physicist, disappears, the Shakleman kids imagine he is merely off on one of his absent-minded wanderings.

But when their father receives a mysterious coded message to meet him, exactly one year later, and then disappears too, they mobilize to rescue them.

Frankly, it's nothing a boy genius and his three resourceful siblings can't handle.