Plan KK (プランKK Puran KK?) was an SR Unit operation aimed at simultaneously eliminating both Kasper and Koko Hekmatyar. It was originally established as Plan K (プランK Puran K?) when Kasper was the sole target but expanded to include Koko when she got involved. Ultimately the operation proved to be the SR Unit's swan song as the unit's commander, Yosuke Hinoki, took advantage of its destruction to make his own break from the organisation. Plan KK is the climactic event of the Castle of Lies Arc.