"Hey, boss? Remind me to show you the pool tomorrow. There's a NO SWIMMING sign on the wall here for a reason."

Galen's head hurt and he was freezing. Oh, and his arms burned, from the shoulder right down to his elbows.

"Wasn't swimming," he managed to say. His brain raced, trying to work out how to explain this to Allie. He settled for, "There's a bomb in there. I tried to get to it, but..."

"Yeah, I found it," Allie said. "That's not all I found, either. Someone tried to blow up the Colony. You interrupted them, and it nearly cost you your life. If it weren't for you, we'd all be dead."

No. That wasn't right. Galen hadn't planted enough explosives to damage more than the space in this room. Halcyon must have done something. "How?" he asked.

Allie pointed at the uranium rods, nestled in some black fabric that looked suspiciously like his wetsuit. "There's enough plutonium there to blow this place twice over. The bomb was a distraction; nothing more. If even one of those rods hit the water, this whole Colony would be nothing but a crater. You must have scared the saboteur away before he could finish the job."

Not he. She. Galen sat up, then wished he hadn't, because the pounding in his head increased in intensity. He flopped back down. No wonder he was cold – he was lying naked on the catwalk. What must Allie think? The shrinkage alone... "Where's my clothes?" he mumbled.

"Your clothes are right where you left them, over there." Allie pointed. "Your wetsuit...well, it tore while I was trying to get you unstuck, so I helped things along a little until I managed to get the wetsuit off you altogether. I might have scraped off a bit of skin getting you out of the pipe, but I wasn't sure how much air you had. I figured you'd forgive me a few grazes as long as I got you out before you ran out of air."

She'd saved him. How, he didn't know, but right now, he didn't care. "Thank you." The heartfelt words just didn't seem like enough. He'd have to think of a way to thank her properly. She'd taken such a risk. If she'd come here while Halcyon was still here, Allie would have been killed like he almost had been. Numbly, Galen pulled on his pants, then his shirt. His hands shook as he struggled with the buttons, but he didn't dare ask Allie for help. She'd done so much already, and she'd nearly...she'd nearly...he'd nearly lost her.

Galen sank to his knees, breathing hard. He wasn't cut out for this sort of thing. He'd never killed anyone in his life. And to think that his attempt to catch the siren so he could keep Allie safe had almost killed her...it made him too dizzy to stand.

"I've dismantled the bomb," Allie said. "The explosives are relatively inert without the detonator. We should still take them back to the Watch as evidence, though. The plutonium is another matter. That's much too dangerous to leave here, but I'll need some sort of shielding for it. The wetsuit's just so I can touch it. That stuff is hot."

Galen pointed a shaking finger at the pump casing. "Take the explosives out of that and put the...what did you say it was?" Uranium. He'd been certain it was uranium. That's what nuclear bombs were made out of, back on Earth.

"Plutonium. The result of the decay of radioactive uranium. Powerful source of alpha radiation with a very long half-life, which is what makes it so dangerous. Especially in water." Allie dumped the explosives into Galen's tool box and bundled the wetsuit with its radioactive contents into the pump casing.

"How do you know that?" Galen asked.

Allie shrugged. "Experience. There was still a supply of plutonium batteries aboard the Human spaceship when they came to the system, and they've been used to power transportation modules. Especially those attempting to be stealthy and operate without engines. Submarines in particular. The easiest way to check if a battery was still good was to measure the temperature. If it was hot, great. If not, the nuclear fuel was spent and it was safe to dispose of."

"But....batteries. Not enough to make much of an explosion, right?" Galen couldn't take his gaze off the pump casing now he knew what it held.

"I already told you. There's more than twice what you'd need to blow this place up. Just one of those would be more than critical mass, under the right conditions, like the ones here. That's why we can't leave it here." Allie shoved the box of explosives into his arms. "Here, you take this and your toolkit. I'll take the payload. I've already called for an aircar that'll be waiting for us when we leave the maintenance corridor, but we'll have to take a skimmer from here. Unless you'd rather walk?"

Galen quailed under her searching gaze. He wasn't sure his legs would hold him. He'd built a nuclear bomb. A bomb big enough to take out the entire Colony and all its inhabitants. He shook his head, trying to dislodge the thought, but it was stuck firmly in his mind. He'd never killed anyone, but he'd nearly killed everyone. To take out one terrorist.

If he'd succeeded, he'd have been worse than Halcyon. Killed more people. Done more damage.

Numbly, he climbed up behind Allie on the skimmer, oblivious to his surroundings. When she took him to the Watch, he'd confess everything. Someone like him should be locked up, where he couldn't hurt anyone. Allie should never have rescued him. She should have left him to drown in the pipe like he deserved.

Genocidal maniac. Mass murderer. Terrorist of the worst kind. Not Halcyon. Him.