In "Cracks Form Within," the Trigger team faces internal strife after a surprising confession shakes the foundation of their unity. Han Do and Oh Soryong are particularly unsettled as they deal with the fallout of this revelation. The episode explores the team's dynamics under pressure, with a focus on trust and betrayal. Meanwhile, they're tasked with solving a case involving a disappearance from twenty years ago, which might just be connected to their current predicament. The episode ends with the team at a crossroads, questioning not just their investigation but their very existence as a unit.