The Flood

"Water is patient, Adelaide. Water just waits. It wears down the clifftops, the mountains, the whole of the world. Water always wins"

When the Tenth Doctor visited Bowie Base One, humanity’s first colony on Mars, it wasn’t long until an alert was raised in one of the headquarters’ remote biodomes.

On investigating, the Doctor and Captain Adelaide Brooke discovered two crew members who had been transformed. With deep cracks around their mouths, a demonic stare and water pouring from their mouths and hands, they were a terrifying sight. Danger intensified when it was revealed that they can infect others simply by touching them with their water.

The Doctor surmised that the ancient race, the Ice Warriors, found and trapped a sentient virus called ‘the Flood’ into a glacier. Newly released, the Flood used a hive mind to control the infected crew with their intended plan to head to and conquer Earth.

The Doctor deducted that the Flood, like the Ice Warriors, have a weakness to heat. He intended to utilise the base’s environmental controls to boil the virus, but when these were destroyed in an explosion, there was only one option left - Captain Brooke and the Doctor left the planet in the TARDIS, and activated a nuclear device destroying the base and all the Flood-infected beings.