Continuity mistake: When Katya and Dove are having it out at the ball, the amount of liquid in Dove's champagne glass continually changes. It starts off nearly empty, then becomes nearly full and goes back to nearly empty. It even gets to the point when she drinks the remainder of the champagne, yet a second later the glass is once again nearly full.
Continuity mistake: In the arm-wrestling scene, one second their arms are to the side, but then, from above, their arms are in the middle, above the line, but then their arms are to the side again.
Continuity mistake: Julian and Becky get to school and see one of their friends sparring a bit. His ex Katie arrives and he tries to kiss her. She pushes him away and then grabs again the strap of her bag, but at the cut she is not holding it anymore. (00:11:50)
Continuity mistake: Major Kang Min-gil in the opening meeting stands up and mentions the meeting when both North and South Korea agreed to build a nuke. The female scientist in the wide shot is leaning with her chin on the back of her hand in the wide angle, but at the mid-sentence cut she has the palm of her hand along her cheek. (00:04:35)
Continuity mistake: When David retrieves the rocket and the great fear chases him through the town, the sun goes from setting to being right above them.