Roger Delacorte called Dr. Spengler, Stantz, and Venkman from Columbia University in response to Alice's encounter with the Library ghost. He was in the Reading Room and observed Peter's prank on Egon. Roger approached them and introduced himself then led them to Alice. He hoped they could clear this issue up quickly and quietly. He listened to Peter's questioning of Alice and became skeptical to which Peter famously replied, "Back off, man. I'm a scientist." After the men touched the etheric plane and fled the library, he ran after them because he still wanted to know if they could solve the problem. Peter yelled they could get back to him. Roger stopped on the stairs.
Roger walked the floor while Egon searched for the library's copy of "The Johansen Argument."
- In the final shooting script, Roger was described as a "choleric, middle-aged civil servant" and introduces himself as the Head Librarian. 
- ↑ Roger Delacorte (1999). Ghostbusters - Chapter 03: "Get Her!" (1984) (DVD ts. 7:20-7:22). Columbia Pictures. Roger says: "I'm Roger Delacorte. Are you the men from the university?"
- ↑ End Credits - Cast
- ↑ Shay, Don (November 1985). Making Ghostbusters, p. 27. New York Zoetrope, New York NY USA, ISBN 0590336843. Roger says: "Hello, I'm Roger Delacorte - the Head Librarian."