“I am not panicking.”

“During a particularly cold Big Freeze she too was sure that . . . aha, the doors are opening!”

Jenna and Septimus crouched down beside Marcellus and watched the doors swing open to reveal a deep, red-tinged darkness. Gingerly, Marcellus leaned forward and looked inside; then he sat back on his heels and beckoned to Jenna to come closer. “Can you hear anything now?” he said in a hushed voice.

Jenna leaned forward through the hatchway into the dark. A sense of being deep inside the Dragon Boat made the hairs on the back of her neck rise. She could smell something like warm iron; it was rich and strange and made her feel a little queasy. “Is this where her heart is?” she whispered.

Marcellus nodded. “Wait a few minutes. Her heart beats slowly when it is so cold.”

Like surgeons gathered around a patient on an operating table, they waited for a heartbeat. Marcellus took out his timepiece and looked at the second hand moving round. It made three sweeps of the dial, then four, then five.

“Nothing,” Jenna said miserably. “Nothing.”

“No,” said Marcellus heavily. “You are right, Princess. Of course.”

“She’s dead,” said Jenna despairingly. “She’s dead.”

“I do not think so. If she were dead I believe she would be frozen all the way through. But possibly she is getting near to it.” Marcellus looked up at Jenna, a serious expression in his eyes. “As your mother so rightly said, only you can save her.”

“But how?”

“It is something the Queens pass down one to another.”

“But no one’s passed it down to me.”

Marcellus was soothing. “I know. But I can tell you. That day in the Big Freeze when my Broda could no longer hear a heartbeat, she went to get my sister Esmeralda, who was Queen. I came with Esmeralda because she always panicked in the Queen’s Way. And I watched what Esmeralda did.” Marcellus gave a wry smile. “And what a fuss she made about it.”

“About what?” asked Jenna, irritated. Sometimes she thought that Marcellus enjoyed being obscure.

“I will tell you.”

By the time Marcellus was nearly through his explanation Jenna had a good deal of sympathy with Esmeralda. So did Septimus.

Marcellus finished with, “So now, Princess, you too must enter the Chamber of the Heart.”

Jenna looked at the reddish darkness beyond the two little doors and for a moment wished that she had never asked Marcellus for help. Like most Castle Queens and Princesses, Jenna had a squeamish side to her, and right then she felt quite sick. But she must do what she must do. She took a deep breath, ducked through the low opening and crept inside, where she found the wide, flat rib that Marcellus had described and crawled gingerly onto it. Below her, Jenna now knew, lay the Dragon Boat’s heart.

Following Marcellus’s instructions, Jenna tipped a few drops of the brilliant blue Tx3 Revive onto her palms and rubbed it in. The fresh smell of peppermint cut through the thick, meaty fug of the Chamber and took away her nausea. She reached down into the darkness, and her hand met something firm to the touch, cool but not ice-cold and not, as Jenna had feared, at all slimy. It felt like touching the side of her horse, Domino, on a chilly night. This was, she knew, the Dragon Boat’s heart. Stretching out both hands, Jenna dropped forward and leaned all her weight onto the heart for a few seconds, then released the pressure. She repeated it twice and then sat back and waited. Nothing happened. Jenna counted to ten slowly and did it again. One . . . two . . . three . . . Once more she waited and once again, nothing happened. Jenna dropped forward for a fifth time and leaned all her weight onto the stilled heart, willing it to respond. One . . . two . . . three . . . wait, count to ten, then ready to begin again. Just as she was reaching the end of her count to ten, Jenna became aware of something happening below in the darkness. A flutter, a twitch . . . and then a low, slow ther-umm pulsed through the Chamber. Jenna was out of the doors as fast as she could go.

“It worked!” she whispered excitedly. “It worked. Her heart just did a beat. She’s alive!”

“A true Queen,” said Marcellus, smiling. “No one else could have done that. I suggest we wait for another beat before we close the doors. Just to make sure.”

They waited. And waited. “Two minutes.” Marcellus’s whisper echoed around the cavern after what had felt like at least ten to Jenna. “Three . . . four . . .”

And then at last—another ther-umm resonated through the Dragon House.