The Battle of the Labyrinth by Rick Riordan

.”
    Tyson frowned. “That funny man has two faces.”
    “The funny man has ears, you know!” the left face scolded. “Now come along, miss.”
    “No, no,” the right face said. “This way, miss. Talk to me , please.”
    The two-faced man regarded Annabeth as best he could out of the corners of his eyes. It was impossible to look at him straight on without focusing on one side or the other. And suddenly I realized that’s what he was asking—he wanted Annabeth to choose.
    Behind him were two exits, blocked by wooden doors with huge iron locks. They hadn’t been there our first time through the room. The two-faced doorman held a silver key, which he kept passing from his left hand to his right hand. I wondered if this was a different room completely, but the frieze of the gods looked exactly the same.
    Behind us, the doorway we’d come through had disappeared, replaced by more mosaics. We wouldn’t be going back the way we came.
    “The exits are closed,” Annabeth said.
    “Duh!” the man’s left face said.
    “Where do they lead?” she asked.
    “One probably leads the way you wish to go,” the right face said encouragingly. “The other leads to certain death.”
    “I—I know who you are,” Annabeth said.
    “Oh, you’re a smart one!” The left face sneered. “But do you know which way to choose? I don’t have all day.”
    “Why are you trying to confuse me?” Annabeth asked.
    The right face smiled. “You’re in charge now, my dear. All the decisions are on your shoulders. That’s what you wanted, isn’t it?”
    “I—”
    “We know you, Annabeth,” the left face said. “We know what you wrestle with every day. We know your indecision. You will have to make your choice sooner or later. And the choice may kill you.”
    I didn’t know what they were talking about, but it sounded like it was about more than a choice between doors.
    The color drained out of Annabeth’s face. “No . . . I don’t—”
    “Leave her alone,” I said. “Who are you, anyway?”
    “I’m your best friend,” the right face said.
    “I’m your worst enemy,” the left face said.
    “I’m Janus,” both faces said in harmony. “God of Doorways. Beginnings. Endings. Choices.”
    “I’ll see you soon enough, Perseus Jackson,” said the right face. “But for now it’s Annabeth’s turn.” He laughed giddily. “Such fun!”
    “Shut up!” his left face said. “This is serious. One bad choice can ruin your whole life. It can kill you and all your friends. But no pressure, Annabeth. Choose!”
    With a sudden chill, I remembered the words of the prophecy: the child of Athena’s final stand.
    “Don’t do it,” I said.
    “I’m afraid she has to,” the right face said cheerfully.
    Annabeth moistened her lips. “I—I choose—”
    Before she could point to a door, a brilliant light flooded the room.
    Janus raised his hands to either side of his head to cover his eyes. When the light died, a woman was standing at the fountain.
    She was tall and graceful with long hair the color of chocolate, braided in plaits with gold ribbons. She wore a simple white dress, but when she moved, the fabric shimmered with colors like oil on water.
    “Janus,” she said, “are we causing trouble again?”
    “N-no, milady!” Janus’s right face stammered.
    “Yes!” the left face said.
    “Shut up!” the right face said.
    “Excuse me?” the woman asked.
    “Not you, milady! I was talking to myself.”
    “I see,” the lady said. “You know very well your visit is premature. The girl’s time has not yet come. So I give you a choice: leave these heroes to me, or I shall turn you into a door and break you down.”
    “What kind of door?” the left face asked.
    “Shut up!” the right face said.
    “Because French doors are nice,” the left face mused. “Lots of natural light.”
    “Shut up!” the right face wailed. “Not you, milady! Of course I’ll leave. I was just having a bit of fun. Doing my job.