Brief Story Line (1st and 2nd paragraph were from the first movie)
Guard (Kim Woo-bin - Our Blues TV series, The Con Artists etc) and Thunder (voiced by Kim Dae-myung (The Drug King, Hospital Playlist TV series etc) were aliens who have been using people on earth as prison for their criminals for many years. They could come back and forth in time to catch those who somehow managed to escape. During one of their mission in 1380, they found a baby and brought her to the year 2012, named her Yi-an (Choi Yu-ri) & raised her for 10 years. But Guard's behavior was very weird and attracted the attention of Min Gae-in (Lee Hanee - Phantom, The Fiery Priest TV series etc), the aunt of a student who was best friend with Yi-an. When the latest batch of criminals were sent to earth, it created complication as they included the rebel Controller who was put inside Detective Do-seok (So Ji-sub - Confession, My Secret Terrius TV series etc) and wanted to turn earth into a place they could live freely but uninhabitable for humans. This could only be stopped by the Divine Blade hold by Guard.