"Heart Signal: Friends" brings together familiar faces from previous seasons of the popular reality dating show, reuniting cast members from "Heart Signal 2" and "Heart Signal 3" in a cozy winter setting. Oh Young Joo, Jung Jae Ho, Kim Do Gyun, Kim Jang Mi, Lee Ga Heun, Park Ji Hyun, Seo Min Jae, and Jung Eui Dong are invited to Signal House, where their relationships will be closely observed. Hosted by Kim Hee Chul, Shindong, Seunghee, and Lee Sang Min, the show promises to explore the potential romantic and friendly connections between the participants. This is a 2021 South Korean variety show produced by Channel A that delves into the dynamics of interpersonal relationships in a unique and intimate setting.

Eight young, single people are brought together at Signal House, a unique reality show where finding love requires subtlety. Participants must navigate romantic connections through discrete "heart signals" without directly confessing their feelings, creating an intriguing social experiment. Celebrity panelists like Soyou (former Sistar member) and Lee Sang Min observe and comment on the unfolding romantic dynamics, adding an extra layer of entertainment to the house's interactions. As love triangles form and dissolve, the housemates compete to find a genuine connection while adhering to the show's strict communication rules. The tension builds as viewers wonder who will successfully pair up and potentially find true love in this unconventional dating environment. This is a 2018 South Korean reality TV/variety show co-produced by Lee Jin Min.