Episode #1.4 - S1-E4
Visible crew/equipment: When Lee is being interrogated, at one point (after the detective says "Are you crazy?") the detective walks towards the large two-way mirror and you can see a clear reflection of a cameraman in the lower part of the mirror. (00:27:31)
Continuity mistake: When Park Eun-hee is talking into a video camera there are some on-screen icons for the camera: zoom, battery level, etc. Initially there are two guide lines on the zoom level bar. When the view changes then switches back a few seconds later, there is only one guide line.