Steins;Gate - episode 12 - 21 Jun, 2011

With the ability to utilize SERN's LHC to compress memories into D-mail size, Kurisu completes her time leap machine, capable of sending one's memories up to two days into the past. However, Okabe, still disturbed by the threatening texts he has received, decides against using the device, suggesting they make their discoveries public instead. As the lab members decide to have a party, Kurisu comes into conflict with Suzuha, who claims she is destined to become a SERN spy, but Mayuri manages to calm things down. While a bomb threat is televised, Suzuha, after hearing about the lab's connection to SERN, flees the lab. Okabe also realizes the danger as Mayuri's pocket watch stops. A group of armed men storm the lab led by Moeka, who reveals herself to be a spy for SERN known as a "Rounder." She orders Okabe, Kurisu, and Daru to be detained while Mayuri, who is deemed as not being necessary, is shot in the head and killed. (Source: Wikipedia)