The May 14 broadcast recorded a peak 7.1% rating, and an average rating of 6.3%, marking OCN's highest rating in its history. The previous record was held by OCN's 'Voice' which recorded a 5.6% rating. Prior to the this, actor Choi Jin Hyuk commented during a press conference that the show 'will exceed 6%' which has come true. He responded to the great news with, "I had just mentioned that in order to encourage everyone to work hard.  It all feels like a dream.  I too have fallen for 'Tunnel', not as an actor but as a fellow viewer," expressing his desires to continue to present a high-quality project.

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Meanwhile, 'Tunnel' is receiving much positive feedback from the masses due to its intricate plot and realistic acting, as fans sit at the edge of their seats waiting for the next episode on May 20.