|Behind the scenes|
- "It all depends on what we mean by 'Terror'. If Clauswitz could say 'War is the last resort of Deplomacy', couldn't we just as well say that terrorism has an equal claim to..."
- ―Hasseldorf [src]
Dr. Hasseldorf was a professional hostage negotiator and hostage situation expert who wrote the book Hostage Terrorist, Terrorist Hostage: A Study in Duality. He is played by George Christy.
Hasseldorf was seen for about a minute in the film when he was interviewed by Gail Wallens on KFLW Channel 5 News. He began speaking about what to expect with the Nakatomi Plaza hostage situation over the next few hours. Hasseldorf said that the hostages would be going through the early stages of the Helsinki Syndrome. Harvey Johnson chimed in and said that he was referring to Helsinki, Sweden. Hasseldorf corrected him by saying that Helsinki is in Finland, and went on to describe that the Helsinki Syndrome basically entails when the hostages will be going through a feeling of dependancy on the terrorists, and the terrorists will feel the same way.