There’s no chance she could hold her own against a monster. I may not be a super-athlete like Gretchen, but Greer looks like a porcelain doll. A minotaur would shatter her into a million tiny designer pieces. She needs help even more than I do.

At least I wear sneakers. Greer couldn’t even run away in those shoes.

“We have an obligation”—I try again, appealing to Gretchen’s sense of duty—“to train her, like you’re training me. What if something happened to her? You’d feel awful.”

She mutters something that sounds like “Hardly,” but then she says, “Look. Nothing’s going to happen to her.”

“How can you know that?”

“You heard her.” She jerks her head up toward the house. “She doesn’t see monsters.”

“So?”

“If she doesn’t see them,” Gretchen explains, “then they won’t see her.”

“But what if—”

“Monsters don’t know who we are.”

“What about the basilisk thingy that attacked me at the bus stop?” I can’t believe Gretchen is being so stubborn about this. It wasn’t this hard to convince her to train me. “She knew I was a huntress.”

“It knew,” Gretchen says with a heavy dose of sarcasm, “that you saw it. You must have reacted to its true appearance in some way. That’s how it knew what you are.”

I want to argue, but I think she might be right. About that night, anyway. That doesn’t mean she’s right about everything.

“What about the ones who’ve seen us,” I press. “They could tell others what we look like, and could mistake Greer for one of us.”

“Unlikely. It’s not like they’re uploading pictures to Flickr or passing around wanted posters with our pictures and a big reward offer.”

“But there is,” I cry. “There’s a bounty on our heads. You heard what the satyr said. They’ve been promised eternal freedom in exchange for our lives. Greer is just as valuable to them as we are.”

She hesitates. Good, hopefully I’ve gotten through. Hopefully she’ll—

“You saw her,” she snaps. “We could be standing side by side and no one could guess we’re triplets.”

Now she’s just being deliberately difficult. I think part of her is jealous, resentful of the obvious advantages Greer has in her life. I think Gretchen’s worried too—she just doesn’t want to admit it. I need to push the right buttons.

“You said yourself, things are getting weird,” I say, trying another tack. “More monsters, monsters at different times. What if other things change?” I grasp for anything that might change her mind. “What if they can start smelling us the way we smell them?”

That gives her pause again. I can see—and almost feel—her considering that possibility. Which only makes me more nervous. Gretchen is a keep-it-together girl. If she thinks that might happen, we could be in really big trouble.

She finally shakes her head. “It doesn’t matter—”

“Doesn’t matter?”

“We can’t make her accept the truth.” Gretchen clenches her jaw. “She made her choice. She doesn’t want anything to do with us.”

“But Gretchen—”

“Forget it,” she says, walking away to the street where her Mustang is parked at an alarming angle. “If you want a ride home, let’s go. Otherwise I’ll see you tomorrow.”

I watch, helpless, as Gretchen disappears down the steep hill. How can she be so heartless? I look back up at Greer’s house—at our sister’s house. A curtain on the first floor flutters back into place.

Greer might be a bit of a snob, but that doesn’t change our blood. She’s obviously been given everything she wants her entire life, so it’s not surprising that she has a superior attitude about things. She probably needs to see the proof that we’re triplets. Next time I’ll bring the records.

At the moment, though, I feel like I need to stay close.

Gretchen might be able to walk away, but I can’t. I’ve only just found my sisters, and I’m not going to leave one of them at the mercy of whatever monster crosses her path. And Gretchen can obviously take care of herself.

Acting like I’m walking away, in case someone is watching through that window, I head around the corner. The house behind Greer’s on the side street has a big, six-foot-high brick wall around the property. As soon as I’m clear from view, I break into a run. Circling around the block, I head into the hilly park across from her house. It’s scattered with dense bushes and shaded by lush trees. A perfect hiding spot.

I climb the concrete steps to the path that gives me a perfect, unobstructed view of Greer’s house below.

As I sink down onto the grassy hillside, next to a thick-leaved bush, I’m not sure about this plan. I’m not sure I even have a plan. I just know I can’t abandon her. Greer may not want anything to do with me, but I’m going to watch out for her anyway. That’s my job, isn’t it? What kind of guardian would I be if I let my own triplet get eaten by a griffin or something on the day we meet?

Besides the fact that Gretchen and Greer are my sisters, there’s a lot more at stake. According to the book, we are the only three girls of this generation of Medusa’s descendants. Always girls. Now I know that we inherited our mythological genes from our biological mother, but I’ve never been able to find out anything about her. There could be aunts or cousins out there somewhere too, I suppose, but the book clearly said there are only three girls born in a given generation.