Contains spoilers for this episode and earlier episodes.
Samsan Tech develops Noongil by combining its image recognition with the Yeong-sil voice service. Interviews with a visually impaired user help the team understand what the app should do, and an early demonstration identifies money aloud. Ji-pyeong questions how the company can pay for a service whose running costs increase with use. He nevertheless supplies possible corporate sponsors, and Dal-mi pursues meetings while keeping her difficulties from the programmers so they can concentrate.
Downloads are initially low, which relieves Dal-mi even as it disappoints her colleagues. Do-san's cousin publicizes his connection to baseball player Park Chan-ho, whose endorsement sends demand upward and makes the funding problem urgent. Won-deok uses the app to read and gives Do-san handwritten feedback. When he passes the notebook to Dal-mi, she discovers her grandmother is losing her sight. She returns home in tears and promises to keep improving the service for her.
Morning Group also presses a complaint over Do-san's broken nameplate. Dal-mi seeks a meeting about sponsorship and finds him kneeling before Chairman Won. Instead of accepting the humiliation, she uses a recording of the earlier meeting to bargain for funding and an end to the complaint. The company gains support for Noongil, but another secret becomes harder to hide. Reading Ji-pyeong's notes, Dal-mi recognizes handwriting that resembles her childhood letters and notices the men's shared supposed birthday.