Warning: SPOILERS for Star Trek: Picard season 1, episode 4.
Zhat Vash, which is out to eradicate all artificial lifeforms in the galaxy. Like the Zhat Vash, the Qowat Milat are also a brand new addition to the Romulan mythos.
The Romulans play a pivotal role in Star Trek: Picard's backstory. Following the events of Star Trek: Nemesis, in which Picard's clone Laris (Orla Brady) and Zhaban (Jamie McShane).
However, the Qowat Milat are unlike any Tal Shiar, which used to be the power behind the Romulan government.
The Romulans are infamously xenophobic, secretive, and duplicitous but the Qowat Milat fly in the face of all of those societal traditions. Instead, the Qowat Milat openly work with non-Romulans such as Picard, though they are strict about their rules and teachings. In contrast to the Romulans' usual paranoid reticence, the Qowat Milat practice what they call "the way of absolute candor", which is a total communication of emotion without any filter between thought and word. In short, the Qowat Milat always say exactly what's on their minds and they are brutally honest. The Qowat Milat also have an inviolate rule about who they "bind their swords" to: the warrior nuns (and Elnor, the only male Qowat Milat) will only fight for someone if it's a lost cause.
The Qowat Milat don't just reject known Romulan values, their openness is also the polar opposite of the emotionless logic practiced by their cousin race, the Vulcans. And, with their elaborate robes and swords, the Qowat Milat resemble the Septas (nuns) in Game of Thrones but mixed with Japanese samurais. The Qowat Milat is a curious hodgepodge which is nonetheless a memorable new addition to Star Trek lore. Star Trek: Picard has already updated the Romulans without raising the ire of Trekkers the way Borg Cube, Star Trek: Picard's Romulan warrior nuns are arguably the most intriguing break yet from the franchise's established portrayal of the Romulans.
Star Trek: Picard streams Thursdays on CBS All-Access and Fridays internationally on Amazon Prime Video.