Hawkins had regained a fragile calm a month after the portal's closure. Christmas lights blinked on the streets, and Hawkins High buzzed with laughter and pop music, the winter dance offering a reprieve from the chaos of the Upside Down. Cassian, dressed in a dark jacket, stood in the gym decorated with fake snowflakes, acting as a chaperone at Hopper's request. His body still felt the effects of teleportation, a skill he now trained with difficulty since the closed portal prevented him from drawing energy from the other side. On an empty lot outside town, he had spent hours focusing, using the essence of his blood as fuel, managing small jumps of one meter, but each attempt left him exhausted.
"This is harder without the portal," he muttered, adjusting his shirt as he observed the students. Mike and Eleven, now Jane Hopper after her adoption, danced awkwardly in the center, their shy smiles lighting up the room. Lucas and Max, more confident, spun together, laughing when Max stumbled. Nancy, in a blue dress, spoke with Dustin near the punch table, her expression soft as she convinced him to dance to cheer him up.
At the police station, Jill organized files, helping Hopper deal with the fallout from Owens' tape. National headlines had exposed the lab's experiments, forcing its closure, but also attracting journalists and federal agents to Hawkins. Jill, with a suitcase ready to leave with Cassian, Helen, and Terri for their next mission, reviewed a final report. "This is a mess," she said, handing a newspaper to Hopper. "They're calling the lab a 'chemical risk.' Murray did well to dilute the truth."
Hopper, with a coffee mug, grunted. "Better that than talking about monsters. But now everyone wants answers, and I'm stuck cleaning up the mess."
Jill smiled, closing a drawer. "You'll manage, boss. You always do."
"And you?" Hopper asked, looking at her. "Where are you going now?"
"Another case," Jill said, evasive. "Helen has contacts who need our… expertise."
Hopper raised an eyebrow. "You and Cassian? You're a strange team."
"It works," Jill said, shrugging. "Take care of Jane, okay? She's special."
"I know," Hopper said, his voice softening. "Thanks for everything, Carter."
At the dance, Cassian approached the punch table, pouring himself a glass. Nancy saw him and walked over, leaving Dustin with Lucas and Max. "Chaperoning doesn't suit you," she said, smiling. "I thought you'd be hunting monsters."
Cassian laughed, taking a sip. "I need a break. Besides, Hopper insisted."
She nodded, looking at the kids. "It's strange seeing them like this, right? Happy, as if nothing happened."
"They won't forget," Cassian said. "But they deserve this night."
Nancy looked at him, her expression serious. "What happened on the porch… I didn't want to complicate things."
"You didn't," Cassian said, keeping his tone light. "We're fine, Nancy. You and Jonathan… that's what matters."
She smiled, relieved. "Thank you. You're a good guy, Cassian."
Before he could respond, Dustin approached, his face red. "Nancy, will you dance with me? Lucas says I don't stand a chance, but…"
Nancy laughed, taking his hand. "Let's go, Dustin. We'll show them they're wrong."
Cassian watched them go, then looked at Eleven and Mike, who shared a shy kiss on the dance floor. "Good job, kids," he murmured, feeling a pang of pride.
At a motel on the edge of town, Helen and Terri prepared for their departure. Terri, reviewing a stolen lab file, frowned. "Look at this," she said, showing a report. "They mention 'residual signals' in the Upside Down. Like something's still active."
Helen, packing a laptop, nodded. "The portal's closed, but that thing… the Mind Flayer… doesn't give up. We need to inform the Vatican."
"And Cassian?" Terri asked, closing her suitcase. "He's exhausted. That teleportation is killing him."
"He's stronger than he thinks," Helen said. "But he needs to train. Without the portal, his blood is all that sustains him."
Terri sighed, looking out the window. "Hawkins felt like the end of the world. What's next?"
"Something worse," Helen said, her voice grave. "There's always something worse."
At the dance, the music shifted to a slow ballad, and Cassian leaned against the wall, watching the kids. Lucas and Max argued about who led the dance, while Mike and Eleven laughed, oblivious to the world. But a strange hum pulled him from his thoughts, an echo that wasn't part of the music. His eyes flashed, and he stepped outside into the December cold.
"Come on, show yourself," he muttered, unsheathing his silver knife.
A stray Demodog emerged from the shadows, its jagged petals snapping. Cassian, focusing, used his teleportation, appearing to the creature's left in a flash. The effort made him dizzy, but he struck the Demodog with a metal pipe he found on the ground, stunning it. The creature growled, emitting a sound that seemed like an echo of the Mind Flayer, a murmur that sent chills down his spine. Cassian teleported again, this time behind it, and plunged the knife into its skull, bringing it down. Panting, he knelt, feeling his body tremble from using his blood as energy.
"What are you doing here?" he said, looking at the corpse. "The portal's closed."
He returned to the gym, cleaning the knife, and found Helen waiting outside. "Trouble?" she asked, noticing his expression.
"A Demodog," Cassian said, holstering the weapon. "It shouldn't be here. Something's not right."
Helen frowned. "Terri found anomalies. The Upside Down is still active. That Mind Flayer… it might be looking for another way in."
Cassian looked toward the school, where the dance lights glowed. "If it comes back, we'll be ready. If Hawkins needs us."
"Promise," Helen said, her voice firm. "But first, rest. You've earned it."
In the gym, the dance continued, oblivious to the danger. Eleven, now Jane, approached Cassian, smiling. "Do you dance?" she asked, half-joking.
Cassian laughed, shaking his head. "Not my thing, Jane. But you, enjoy it."
She nodded, returning to Mike. Cassian watched them, then looked at Nancy, who danced with Dustin, her laughter filling the air. Lucas and Max, now more relaxed, playfully pushed each other on the dance floor. For a moment, everything seemed normal, but the murmur of the Demodog echoed in his mind.
At the station, Jill finished packing, looking at Hopper. "If you need anything, call us," she said, handing him a number. "We'll come as soon as possible."
Hopper nodded, pocketing it. "Keep an eye on Cassian. That kid gets into too much trouble."
"Someone has to," Jill said, smiling before leaving.
At the motel, Terri closed her laptop, looking at Helen. "Do you think Hawkins will be okay?"
"For now," Helen said, slinging her bag over her shoulder. "But the world is bigger than this town. And so are the problems."
Cassian, back in the parking lot, looked at the stars, the cold biting his skin. The Upside Down was silent, but in that other dimension, the Mind Flayer watched the school, its shadowy tendrils moving like a patient predator. Cassian tightened his grip on the knife, sensing another hidden presence waiting for the right moment to appear.