November 15, 2145

November 15, 2145, is an important date in the story of Doom 3. The game mostly takes place during that date.

Events
During this day, Counsilor Elliot Swann and his bodyguard, Jack Campbell, arrive on UAC Mars Research Facility, along with a new Marine. Swann is immediately directed to Dr. Malcolm Betruger to discuss about the recent "problems" Betruger's research has had. Unknown to most personnel, Betruger had been conducting research on portal technology, and another scheduled test was to take place later that day. While Betruger and Swann discuss, the Marine overhears their conversation. The Marine is sent by Sergeant Kelly to find a missing scientist in an old decommissioned comm facility. The scientist is Dr. Jonathan Ishii, who is attempting to warn Delta Lab scientists about what lies beyond the test portal. But before he is able to send the transmission, the Marine arrives and the transmission is not sent before the portal test suffers a seemingly serious failure. As soon as the failure occurs, Hell bursts out from the portal, and within minutes, over 90% of the personnel in the facility are either dead or zombified. Dr. Ishii also turns into zombie, and Marine is forced to kill him. Demons start infesting facility. He then receives an order to return to Marine HQ for further orders.

Marine then receives an order to link up with Bravo Team and get to the Communications Facility to send a transmission to UAC fleet orbiting earth for reinforcements. However, Swann and Campbell, who have survived the initial wave, are trying to stop the transmission in order to isolate Mars Facility from everyone else, in order to protect Earth. Marine eventually reaches Comm Facility and Swann contacts him to stop the transmssion. The Marine can then choose whether to send the transmission or not.

Whichever Marine chooses, he will then makes his way to Delta Labs, the starting location for the invasion. However, he falls to recycling facility. In here, Marine learns that Betruger is in league with the demons now, and he intends to bring the fleet from Earth to Mars, and use the ships to bring Hell to Earth. After escaping recycling facility, Marine reaches Delta Labs. There, he finds Dr. Ian McCormick, who explains him that the invasion was not an accident, but Betruger unleashed it after he went through the portal with the Soul Cube, an artifact found in the Mars archeological dig site. McCormick helps the Marine reach Delta Labs - Level 4 and the main portal. However, Betruger set a trap for him and Marine gets sucked into the portal. The events of the game during November 15, 2145, end here.

Trivia

 * The date is also mentioned in the beginning Doom 3: Resurrection of Evil, with the following text:
 * November 15, 2145: The UAC Reseach Facility in Mars suffer a serious mechanical failure during a scheduled experiment, resulting in a complete destruction of the facility. Only one survivor is located.