John tries to slip unobtrusively through the Rio carnival crowd, dodging revellers and slapping the hands of pickpockets with the skill of long practice. Behind him something powerful is coming, its aura so bright he's afraid to look too closely, moving through the crowd like a shark through custard. It's a weird simile, the tag-line of an old joke, but it keeps crossing his mind. He's still trying to stay ahead when he runs into the wall.
She doesn't look like a wall; she's a brunette, about twenty and a foot shorter than he is, but somehow he knows he isn't going to get past her. Maybe it's the way he bounces when he runs into her. She doesn't say anything.
"Scusi, signorina..." It's a horrible accent, and even John knows it. He tries to dodge to one side, she effortlessly matches the movement and says "Wanna dance?"
"Nice try, John," says a familiar voice behind him.
"Nice to see you too, John," says Ripper, as Constantine turns toward him. Ripper isn't the source of the magic John's sensing, though there's a faint echo of it in his aura. Someone else... The redhead steps out of the crowd behind him, a symphony of dark leather and lace, and raises an eyebrow. It's worse than John had feared, much worse.
"So..." says John, shakily lighting a Silk Cut. "How long since she turned you, Ripper?"
"Told 'ya so, Giles," says the redhead, then to John: "You're not from around these parts, are you?"
He backs away from her, and runs into the wall again. The brunette has him by the arm, a grip like a vice. "Relax," says Ripper, "we really don't plan to hurt you, you pillock."
"Yeah, sure you don't."
"He thinks Willow's her evil twin," says the brunette. "The queen of the damned."
"Is that it?" asks the redhead. "You're from the world where the Master took over Sunnydale?" John realises that she's breathing, and sags as a wave of relief washes over him.
"What happened here then?" asks John.
"We kicked his ass, of course. Or rather Buffy did."
"The Slayer. You know, one girl in all the world?"
"Oh bloody hell," says John, staring at Ripper. "You're a Watcher?"
Ripper frowns, and says "Always. But I thought I was in that world too."
"You? A watcher? You have to be joking. You dropped out of college and joined the RAF. Your dad disowned you, last I heard you were a squadron leader."