"Circle" once again proves that there is merit to a shorter series with an episode so packed that keeping up and grabbing onto every little tidbit of information is challenging. In 2017, Woo-jin gets a new study partner who challenges his hard-earned normalcy. In 2037, Joon-hyeok dives deeper into the stabilization chip and its true function. It looks like our seasoned hero holds the key to all mysteries.
Whether Woo-jin's (Yeo Jin-goo) new friend is the alien or not is the current mystery in 2017. That and whether her convenient approach during class is deliberate, of course. The episode also takes its time to establish Woo-jin's identity as Joon-hyeok (Kim Kang-woo) and noticing the little details which achieve that is highly entertaining. From the Rubik's cube to pinching a young Lee Dong-soo's (Jeong Joon-won) eyelid, the series makes it clear in a fun way.