Invasion of Manhattan

The Invasion of Manhattan, (TV: Evolution of the Daleks) also known as the Dalek-Human Hybrid Incident, (PROSE: Dalek Combat Training Manual) was an attempted invasion of Manhattan in 1930 by the Dalek Cult of Skaro, led by Dalek Caan, after they overthrew Dalek Sec. Having converted over a thousand humans into Dalek-Humans, the Daleks' planned to convert the rest of Manhattan's population in what they intended to be the first stage of the conquest of Earth. However, the invasion was thwarted when the Dalek-Humans, having been imbued with the Tenth Doctor's Time Lord DNA, turned against the Cult of Skaro and destroyed Daleks Thay and Jast. In response, Dalek Caan remotely terminated all the Dalek-Humans before initiating an emergency temporal shift to escape. (TV: Evolution of the Daleks)

The Time War-era Time Lords saw a node of this event, teaching them that Sec seemed to be the most open of the cult to new ideas, while the other three members defaulted to typical Dalek responses when faced with such options, and that the group's individuality could cause strife amongst them. Recognising that the human-hybrid Sec knew much about Dalek strategy while also being welcome to emotions, the military, despite seeing the node foretell Sec's death, sought permission from the High Council to extract the Human-Dalek from that moment in the timeline, hoping to recruit him. (PROSE: Dalek Combat Training Manual)