Sensing trouble, Mr. Manning began to roam the aisles as he talked about mass and universal gravitation. Bridget’s attention soon returned to the fine thread of sound connecting her to another, far more interesting, world.

The audiobook’s narrator had moved on to the hunt for the baby. In her mind’s eye, Bridget was beside the assassin as he snuck down an alley. Together they looked up, trying to spot foot- and handholds in the rough wall. Once he climbed into the attic room, the assassin planned to kill Jancy, the newborn baby now lying in the arms of her mother, a serving girl named Margarit. It was Margarit’s misfortune that one night, nine months ago, she’d caught the king’s eye. And that a seer had prophesied one of the king’s children would grow up to overthrow him.

The only solution seemed to be to order the murder of his own offspring, but the king had balked. When it came to his illegitimate children, Queen Jeyne was not nearly as squeamish.

“Newton began developing the laws of motion when he was only twenty-three. Just six years older than you guys,” Mr. Manning said. “Derrick, can you tell me the first law of motion?” He liked to randomly call on students.

Derrick, a tall, skinny guy with a bad complexion, straightened up. Bridget had never talked to him, but she knew who he was. Everyone at school did—for all the wrong reasons.

“Basically, it says a body at rest will remain at rest, and a body in motion will remain in motion, unless they are compelled to change by an outside force.”

Walker made a sotto voce comment about bodies in motion, but Bridget paid no attention. The book was approaching one of her favorite scenes. The voice in her ear painted a picture of a cramped room, barely big enough to hold a straw-stuffed mattress. The low ceiling forced the assassin to stoop as he crept forward. The image was so vivid that Bridget reflexively hunched her shoulders. On the bed a sleeping Margarit lay curled around her baby. She was a long-legged, milk-white girl of some six-and-ten years. A healthy wench, to look at her. At least, the narrator warned, she would be until the assassin’s dagger entered her heart.

A dagger. Was this dagger in the database? Bridget jotted in the notebook hidden under her classroom notes. R. M. Haldon’s fantasies were famous for the wide variety of weapons the characters wielded, from dirks to double-bladed axes to the misericorde, a long narrow knife used to deliver a merciful death to gravely wounded knights.

Even though she was focused on the details, the overall story still enthralled Bridget. It didn’t matter that she’d heard or read it more than a dozen times before. That she knew how the assassin’s mission would fail, or how the blind seer’s prophecy would come true in surprising ways.