- Directors: John Guillermin, Irwin Allen
- Producers: Irwin Allen
- Writers: Novel, Richard Martin Stern, Thomas N Scortia, Frank M Robinson, Screenplay, Stirling Silliphant
- Genres: Action, Thriller, Drama
- Actors: Steve McQueen, Paul Newman, William Holden, Faye Dunaway, Fred Astaire, Susan Blakely, Richard Chamberlain, Jennifer Jones, O J Simpson, Robert Vaughn, Robert Wagner
Architect Doug Roberts (Paul Newman) arrives from a vacation for the dedication of the newly completed Glass Tower (which he designed) in San Francisco. At 138 stories, the skyscraper is the tallest building in the world and a dedication party is planned. Upon his arrival by helicopter, he meets building financier Jim Duncan (William Holden). Duncan reveals his plans for additional skyscrapers across the U.S., but Roberts wants to focus instead on building communities in rural areas, which causes friction with his girlfriend Susan Franklin (Faye Dunaway) who has been given a major promotion for the magazine she works for and wants to stay in the city. During a romantic rendezvous between Roberts and Susan, building technicians in the main utility room conduct a routine check of the building’s electrical systems. During the check, a circuit breaker unexpectedly shorts out and sends a power surge up into the building, culminating in the building’s relay system breaker shorting out in a storage room on the 81st floor, causing a small fire that stays contained and unnoticed due to a combination of a lack of accelerants and the shortcomings of the building’s security systems. Roberts is notified and presents a scorched wire from the utility room breaker to Duncan, who is baffled by the flare-up. Roberts goes to confront chief electrical engineer and Duncan’s son-in-law Roger Simmons (Richard Chamberlain) over the flare-up. During a tense meeting with Roberts at Simmons’ house, Simmons pleads ignorance and insists to Roberts that the building is up to code standards but does not admit to changing Roberts’s specifications. Roberts is skeptical of the building’s electrical system and demands Simmons bring the specifications to his office the next day and heads back to the building.
Outside the building, Roberts comments to Susan that he is unsure what will become of the building, but that perhaps it should be left alone as a symbol of the world’s problems. O’Hallorhan joins them and states that though fewer than 200 people died, the casualties could have been much worse, and a worse disaster is possible if builders and architects are not willing to take fire safety and fire fighting into account more seriously with skyscrapers. Roberts looks up at the charred skyscraper and promises to consult with O’Hallorhan on such matters in the future.