Complex sentence: After a brief confrontation, the Skrull is about to reveal where Danielle is when another agent shoots the Skrull in the head, leaving Jessica convinced Skrull Jarvis is going to kill Danielle.
Split into simpler sentences: After a brief confrontation, the Skrull is about to reveal where Danielle, is when another agent shoots him in the head. Jessica is then convinced Skrull Jarvis is going to kill Danielle.