The movie telegraphed these things (spoilers)
- When the Asian lady decides to drive Agent Harker home (and stay in the car), you just know she was going to die. They would have had Blair Underwood in that scene if they weren't planning to have someone die. The movie doesn't have too many characters, so this Asian FBI lady was probably their only pick
- The movie makes clear Longlegs schtick involves little girls and their birthdays. So when Agent Harker meets Agent Carter's sweet daughter and discusses a birthday party, you could easily predict that the daughter would become one of the targets at the end