Eventually, the wreckage had become his obsession.

It had started harmlessly enough. A lunch break spent working through the scanner reports. An air of distraction over dinner, as if something visible only to him were catching his eye. But as the weeks progressed, her brother’s preoccupation had slid into darker territory.

“It’s not just a signal,” he had whispered to her, eyes darting cautiously to the adjacent empty desks in the workshop. “The wreck’s actively communicating with us! I missed it before, but look.”

Harrison placed his tablet onto her desk, on top of the schematics she’d been reviewing. His hands had a slight tremble, she noticed.

“It’s a two-way exchange, Clarissa. Look: the wreck’s responding to our attempts to scan it.” He zoomed in to a point on his timeline, which he’d adorned with colour-coded annotations, links to datasets, sound files displayed as waveforms. Clarissa felt her skin prickle with apprehension.

“This is why the readings made no sense!" he continued, breathlessly. "Each set of readings is just a response to whatever we sent two days before. It’s all spoofed. It’s like a conversation in a slow motion."

She’d stood up at the point. She’d turned to face him, taken his hand, and asked if they could talk it over later, somewhere less open. Privately she’d been thinking about therapists, trusted colleagues, anyone else who might be able to reason Harrison out of his frenzy - or at least calm him down. But he’d been having none of it.

“You’re not listening,” he’d hissed, eyes again darting to the desks next to Clarissa’s. “I think someone else knows. Someone else on the Comms unit, maybe. I’m - I think I’m being followed, Clarry.”

The use of his childhood nickname for her had taken her off-guard, and annoyed her. She’d raised her voice at that point, told him he was being impulsive and irrational, and that she didn’t want to hear any more about it. This had been more effective than she’d intended; he stepped away from her, tablet now clutched to his chest, his breathing deep.

She’d never forgot his expression at that moment. He’d looked at her with a mixture of sadness and grim satisfaction. As if another of his wild theories had been vindicated. *You’re in on it too, aren’t you?* his face seemed to ask.

And that had been the last time she saw him. He hadn’t answered his door when she ascended to his lonely spot on the habitat ring later that evening, nor had he switched on his terminal. The next day he wasn’t anywhere on the Comms deck, and no-one had seen him since the previous evening. He’d vanished.