You keep your distance as Agent Lang heads to the back of the RSL building. It’s a small, unassuming place, made of white brick with a neat garden and a flagpole out the front with the flag of the Returned Services League.

The next minute, he tosses his communicator on the ground and shoots it. You watch as his signal drops out on your tracking device. It’s designed to bring you here.

You creep closer and hide behind the wall of the building. Peering around the side, you see a circle of bricks in the parking lot behind. Lang presses on one the bricks and the floor of the circle drops away to create a gaping hole in the ground. Is it a doorway? A lake? Either way, it’s using technology not from this Earth. You watch as Lang rounds the corner away from the hole and out of sight.

You creep towards the edge of the circle. The sides slope down to the water below. It’s a pool of darkness in the earth, filled with a strange black liquid that’s churning and writhing. Those aren’t eels down there, but something far more dangerous.

You slip a cryofreeze detonator from a bag on your belt and into your pocket and keep it there, loaded and waiting. Just in case.

“Lang!” you call, “Where are you?”

You back away as he rounds the corner. He moves towards you with an easy step and a smile, but there’s something strange about his eyes. Bright, glowing blue, the same as the postie who was infected. You keep the pool between yourself and him. “What happened? Your signal dropped out.”

“I’m fine,” says Lang, “I’ve found out all about it. They’re parasites, like we thought, they spread through the pipes and the water supply. This is their nursery.” He points towards the pool of dark water and a fond smile spreads across his face. “Look at them. Cute little buggers, aren’t they?”

You notice Lang creep closer and you put your hand in your pocket.

“How’d you get all this information?”

“I asked them. They’re happy to share. They just need a host to multiply…”

You shake your head. “No.”

“Get in the water, Agent.”

He’s pointing a raygun at you. He doesn’t realise you have a plan.

“They have a mother, don’t they?” you prod, taking an obedient step towards the water.

Lang nods dreamily. “She sleeps down there. You’ll meet her soon. It doesn’t hurt at all. Trust me.”

You take another step. You can feel the water lapping around your ankles and the thrashing of tendrils as the creatures’ swarm.

“You once told me not to trust anyone.” You pull the detonator out of your pocket.

Lang’s face twists into an expression of terror. “No!”

He lunges across the pool towards you, but you’ve already dropped it. You turn aside just in time as the device explodes. The detonator plummets into the water, freezing everything it touches, and your shoulders are dusted with black ice from the impact. Lang is caught with them, his face fixed in a scream.

You press your communicator with a shaking hand.

“Commander… I’ve destroyed the parasite hive. Agent Lang is down.”