Oxygen is 1999 film, directed and written by Richard Shepard. The film follows a troubled and (unbeknownst to her husband) masochistic cop, Madeline Foster (played by Maura Tierney) as she pursues a kidnapper who calls himself Harry Houdini (Adrien Brody). The film bears a resemblance to the 1958 film Macabre.

"Harry Houdini" (Adrien Brody) has kidnapped and buried alive a rich businessman's wife. He demands $1 million in cash from the woman's husband in return for the release of the location of her burial site before she runs out of oxygen. He also states that if police involvement is initiated, he will ensure she is never found alive. As expected, however, police involvement is initiated and Detective Madeline Foster (Maura Tierney) is assigned with the task of finding the buried woman as soon as possible, together with catching Houdini.

It is quickly realized though that Houdini, in fact, wanted the police to get involved so he could commit a second kidnapping - that of Foster. When Houdini is finally caught as the result of a car chase involving him and Detective Foster, he embroils her into his terrifying psychological world as she attempts to get him to reveal the location of his buried victim. When Foster's initial interrogation of Houdini proves unsuccessful, the FBI are assigned to take over the case, although they do not have any more luck. In a plot twist, it is revealed that Houdini has already committed a murder, that of his accomplice. He now has nothing to lose and the police realize the death of the buried woman would not be as significant as first thought.

Oxygen ( /ˈɒksɨdʒɨn/ OK-si-jin) is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς (oxys) ("acid", literally "sharp", referring to the sour taste of acids) and -γενής (-genēs) ("producer", literally "begetter"), because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a very pale blue, odorless, tasteless diatomic gas with the formula O₂.

Oxygen is a member of the chalcogen group on the periodic table and is a highly reactive nonmetallic element that readily forms compounds (notably oxides) with almost all other elements. Oxygen is a strong oxidizing agent and has the second-highest electronegativity of all the elements (only fluorine has a higher electronegativity). By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium and the most abundant element by mass in the Earth's crust, making up almost half of the crust's mass. Free oxygen is too chemically reactive to appear on Earth without the photosynthetic action of living organisms, which use the energy of sunlight to produce elemental oxygen from water. Elemental O₂ only began to accumulate in the atmosphere after the evolutionary appearance of these organisms, roughly 2.5 billion years ago. Diatomic oxygen gas constitutes 20.8% of the volume of air.