Name: The Flood
Format: Television show
Time of Origin: Mars; originally in the time of the Ice Warriors; The Doctor faced it in 2059.
Appearances: “The Waters of Mars”
Doctors: Tenth Doctor
Companions: Adelaide Brooke
One of The Doctor’s most dangerous and mysterious adversaries, ‘the Flood’ – as it was referred to by the show’s producers – was essentially a highly dangerous virus of ambiguous sentience.
Based on all available information, the Flood was a highly-evolved virus, capable of transmitting itself after infecting a water supply and subsequently spreading through such diverse means as consumption to simple physical contact. Its full history – such as whether it was a natural evolution or an artificial creation of some kind – is unknown, but it was apparently frozen in an ice field under a large crater by the Martians in their distant past, demonstrating the ability to understand Ancient North Martian (The Doctor speculated that the Ice Warriors had contained the Flood, but his words don’t rule out the possibility that they created it).
Hosts of the Flood appeared to have been completely drenched in water regardless of the amount they had been initially exposed to – one person was infected by nothing more than a single drop of Flood-contaminated water landing on his cheek -, the skin around their mouths appearing broken and their irises turning white. Based on scans of the victims, those afflicted with the Flood had lower-than-normal pulses and their brain activity was simply described as ‘haywire’. Their host’s physical speed was also greatly increased, to the point where The Doctor and Adelaide Brooke had to use an accelerated robot in order to escape being caught by the Flood’s first hosts while they tried to escape their first attack.
Now ‘breathing’ water, the Flood had no need for oxygen, with one member of the base speculating that they generated their own internal fission to cope with the cold temperature as they briefly walked outside the base, also being capable of generating water as an offensive weapon. Their hosts appeared to be vulnerable to electricity, although this could have just been an extension of humans’ natural weakness to electricity rather than something specific to the Flood, particularly since it only incapacitated the shocked host for a few seconds. The Doctor speculated that the virus was particularly effective because the human body was at least 60% water, but it is uncertain how this would affect its use of other species as hosts.
It was unclear if the Flood was sentient; some of its hosts were capable of speech, but this ability was only shown in the early stages of infection when it may have been drawing on the host’s memories of language rather than its own ability. Subsequent ‘communication’ between Flood-infected hosts was limited to a high screeching that could have been nothing more than a signal they sent to other hosts to attract attention, similar to wolves howling. During this brief period of ‘lucidity’, the Flood expressed an interest in spreading to Earth to infect the water supply there, suggesting that they require other sources of water rather than possessing a limitless amount on their own, although they still clearly controlled a great deal of water. The rate of infection varied between being instantaneous to taking some time, with the Flood apparently delaying symptoms in the host to allow it to spread, although other victims were apparently able to resist the infection long enough to take some kind of action.
Having been apparently trapped by the Martians in the distant past, the Flood remained unknown until the crew of Bowie Base One, Earth’s first offworld colony, landed on Mars in 2058, setting up base directly over the ‘iceberg’ where the Martians had contained the Flood. Despite this, it took over a year for the Flood to infect the base, only spreading to the human population when the water filters in the bio-dome where the base’s food supplies were grown – ran out and there were no decently-sized replacements available, resulting in the bio-dome’s water supply becoming infected and the virus soon spreading to the crewmembers in the dome At the time.
Accompanied by The Doctor – who had arrived at the base by accident and was forced to remain despite his attempts to leave as the events of this date were a fixed point in time and space that he shouldn’t alter -, Adelaide Brooke, the base commander, determined the extent of the threAt they faced, but found herself facing an ever -escalating threat as the virus threatened to spread. With the base locked down, the Flood’s hosts were able to use the maintenance shafts to climb inside the dome and reach the roof of the base, subsequently generating sufficiently powerful blasts of water to penetrate ten feet of steel, infected water spraying throughout the base and cutting the crew off from the rocket.
With the mission’s second-in-command having been forced to destroy the rocket after he was infected to prevent the Flood returning to Earth, the Flood’s hosts apparently attempted to ‘summon’ the Flood from the glacier, generating a scream of some sort. With only three members of the crew left alive, The Doctor – having become too emotionally invested in the crisis despite his knowledge that it was a fixed point in time – used one of the base’s robots to head to the TARDIS – unable to go there himself because his spacesuit had been damaged and the other suits were blocked off by the Flood -, using the robot to remotely pilot the TARDIS to rescue him, Adelaide and the base’s last two survivors, the ship arriving mere moments before the Action Five nuclear detonation could complete itself. With the destruction of Bowie Base One, it is possible that the Flood itself was destroyed in the explosion, although this is uncertain at best, and its possible existence on Ancient Mars creates the possibility for it to return in future.