In an underwater facility, a team of scientists is doing research on mako sharks to help in the re-activation of dormant human brain cells like those found in Alzheimer's disease patients. After one of their sharks escapes the facility and attempts to attack a boat full of teenagers, financial backers send corporate executive Russell Franklin to investigate the facility. In the laboratory, doctors Susan McAlester and Jim Whitlock prove their research is working by testing a certain protein complex that was removed from the brain tissue of their largest shark. However, Jim's right arm is bitten off by the animal shortly afterwards. Brenda Kerns, the tower's operator, calls a helicopter to evacuate Jim, but as he is being lifted, the stormy weather causes Jim to fall into the shark pen. The shark then grabs Jim's stretcher and pulls the helicopter into the tower, killing Brenda and the pilots.
In the laboratory, Susan, Russell, wrangler Carter Blake, marine biologist Janice Higgins, and engineer Tom Scoggins witness the shark smashing Jim against the laboratory's main window, drowning him and flooding the facility. With few options left, the group goes to the facility's wet entry, where they plan to take a submersible to escape. Upon being confronted, Susan confesses to the others that she genetically engineered the sharks to increase their brain size, as they were not large enough to harvest sufficient amounts of the protein complex; this has the side effect of making them smarter and deadly. When the group reaches the wet entry, they discover that the submersible has been damaged. While delivering a monologue emphasizing the need for group unity, Russell is dragged into the submersible pool by the shark and killed.
The remaining members opt to climb up the elevator shaft at the risk of destabilizing the pool. In the process, Janice loses her grip and falls into the shark-infested water. Despite Carter's attempts to save her, the shark ultimately kills her. In the facility's kitchen, which has been partially flooded, cook Sherman "Preacher" Dudley manages to kill another shark with an explosion. He then makes his way to the elevator shaft, where he encounters Carter, Tom and Susan. Carter and Tom go to the flooded laboratory to activate a control panel that drains a stairway to the surface, while Susan heads to her room to collect her research material. Carter and Tom reach the control panel, but the largest shark kills Tom, destroying the controls. In her room, Susan is ambushed by another shark, but manages to kill it with a power cable, destroying her research in the process.
After regrouping, Carter, Susan and Preacher go to a decompression chamber and swim to the surface. Carter realizes that the sharks made them flood the facility so they could escape through the weaker mesh fences at the surface. In an effort to distract the last shark from escaping to the open sea, Susan cuts herself and dives into the water. Carter dives in to try to save her, but is too late. While Carter is grabbing hold of the shark's dorsal fin, Preacher shoots the shark with a harpoon, but the spear also goes through Carter's thigh. As the shark breaks through the fence, Carter orders Preacher to connect the trailing wire to a battery, sending an electric current through the wire and to an explosive charge in the harpoon, killing the shark. In the end, Carter managed to free himself in time, and joins Preacher to see a workers' boat en-route on the horizon.Saffron Burrows as Susan McAlesterThomas Jane as Carter BlakeLL Cool J as Sherman "Preacher" DudleyJacqueline McKenzie as Janice HigginsMichael Rapaport as Tom ScogginsStellan Skarsgård as Jim WhitlockSamuel L. Jackson as Russell FranklinAida Turturro as Brenda Kerns
Deep Blue Sea was inspired by Australian screenwriter Duncan Kennedy after he witnessed a "horrific" shark attack on a beach near his home. The tragedy contributed to a recurring nightmare of him "being in a passageway with sharks that could read his mind". This motivated him to write a spec script, while acknowledging the challenge of approaching a shark movie without repeating Steven Spielberg's 1975 classic Jaws. Although Warner Bros. bought the script in late 1994, actual development on the project did not start until two years later. When Renny Harlin was chosen to direct the film, Kennedy's screenplay, which had already been re-written by several writers at Warner Bros., was presented to Donna Powers and Wayne Powers, who turned it into the film's final script. According to Wayne, "The movie became essentially what we wrote. The draft we were first presented by [Warner Bros.] was much more of a military espionage, high-tech action movie, grenade launchers, that kind of thing. We wanted our team to include more blue-collar types and not to have weapons to fight back, to play it more as a horror film."
Deep Blue Sea had a budget of $82 million and represented a test for Harlin, who had not made a commercially successful film since Cliffhanger in 1993. Harlin's main goal was to bring the horror genre back to the serious and high-budget production values of films like The Exorcist, Jaws, The Shining, as opposed to the tongue-in-cheek style of subsequent films in the genre. Ridley Scott's 1979 film Alien was an influence on the casting process, as Harlin wanted to cast the characters in a way as to make it impossible for the audience to know who was going to die or survive. To achieve this, he combined relatively unknown actors who could deliver solid performances and meet the physical demands of the diving and stunts with a star, Academy Award nominee Samuel L. Jackson, who "anchors the whole piece". Harlin also forced the studio into hiring rapper LL Cool J because he wanted a character who could bring "a lot of warmth and humor to the film without it being joke-type humor".
Principal photography for Deep Blue Sea began on August 3, 1998. Most of the film was shot at Fox Baja Studios in Rosarito, Mexico, where the production team constructed sets above the large water tanks that had been built for James Cameron's 1997 film Titanic. Some of the sets were designed so that they could be submerged, while others were built on sound stages with fishtanks used as windows. At Fox Baja Studios, the cast worked with sharks that were either animatronic or computer generated. As the shark used in Jaws was 25 feet long, Harlin decided to increase their animatronic shark to 26 feet. Jackson recalled, "When they first brought it into the lab we were all in awe of the size of this machine [...] It was a real monster. I would walk up to it slowly and touch it and they said it felt like a real shark. The gills moved and it had a mind of its own sometimes." As an added homage to Jaws, the license plate pulled from the shark's teeth by Carter is the same plate found in the tiger shark carcass from Spielberg's film.
After the shoot at Fox Baja Studios wrapped, Harlin insisted the team go to The Bahamas to shoot with real sharks. Recounting his experience there, actor Thomas Jane, who played shark wrangler Carter, said, "The first day, I was in a cage, but the next day, they swam me 30 feet down... Then this guy yanks the breather off me and the water's churning with blood and guts and stuff... It was so terrifying that I don't want to remember it." The idea was to mix footage of real sharks with animatronic and computer generated sharks to ensure a seamless transition between them all. To distinguish Deep Blue Sea from Jaws, where the shark is frequently hidden, Harlin decided to show theirs more prominently because he felt that audience expectations had changed since then.
The scene where the cast is trying to get back to the elevator after hooking up actor Stellan Skarsgård to the helicopter is actually an accident that made it into the finished film. As Jackson explained, "At one point three tons of water got thrown on us by accident and we got swept toward those cargo bays and everyone thought we were going into the drink and people were tumbling around this metal grating [...] We scrambled up and kept acting [...] That was not supposed to happen and we didn't have safety harnesses on and we were flailing around on this deck." Jackson was initially offered the role played by LL Cool J, but his management team did not like the idea of him playing a chef, so Harlin created the role of Russell Franklin for him. Additionally, LL Cool J's character was supposed to die early on, but the director ultimately decided to keep him. The production team could not afford to have a fully trained parrot for LL Cool J's character, so they used two parrots: one that was good at flying, and another that could sit on his shoulder.
The film's ending was changed shortly before its theatrical release. Originally, Burrows's character would escape the shark infested water and live. However, the test audience, who saw the film less than a month before its release, disapproved of the ending because she was behind the shark experiments and was seen as the film's villain. As a result, the production team did a one-day reshoot in the Universal Studios tank and did some computer generated work on the sharks to change it. In 2009, Harlin explained that Deep Blue Sea was the hardest film he had ever made because most of the shooting days involved the team standing in water or being under water for long periods. According to him, "Just the practicality of putting a wet suit on in the morning, being in the water all day. Your script, all your paperwork has to be made of plastic paper. And things that you wouldn't think would ever float, they float. [...] Or then things that you hope would float actually sink and you can't find them anywhere."
The film score for Deep Blue Sea was composed by Trevor Rabin. Rabin's music ranges from orchestral and choral arrangements to electronic soundscapes, and was noted for its use of both dramatic and easily accessible themes. The soundtrack features two songs by LL Cool J—"Deepest Bluest (Shark's Fin)" and "Say What"—which were used in the end credits. Two soundtrack albums were also released for the film. The first album, Deep Blue Sea: Music from the Motion Picture, was released on August 3, 1999 by Warner Bros. Records and features a set of hip hop and R&B tracks by several artists, including Hi-C, Cormega, and Bass Odyssey. The second album, Deep Blue Sea: Original Motion Picture Score, was released on August 24, 1999 by Varèse Sarabande and contains musical tracks by Rabin.
Deep Blue Sea performed well when it opened on July 30, 1999 in 2,854 theaters, finishing third and grossing around $18.6 million at the US weekend box office. During its second weekend, the film grossed an estimated $11 million and finished in fifth place, behind The Sixth Sense, The Blair Witch Project, Runaway Bride, and The Thomas Crown Affair. Overall, Deep Blue Sea went on to make $73,648,142 in the United States and Canada, and $164,648,142 worldwide. The film's performance was compared to Stephen Sommers's The Mummy and Jan de Bont's The Haunting, which had a similar budget and made a significant impact on the box office in the summer of 1999.
Deep Blue Sea received generally mixed reviews from critics. Rotten Tomatoes, a review aggregator, surveyed 92 reviews and judged 57 percent to be positive; the site consensus states, "Aside from a few thrills, Deep Blue Sea is unoriginal and unintelligent." On Metacritic, another review aggregator, the film has a score of 54 out of 100, based on 22 critics, indicating "mixed or average reviews".
Writing for Chicago Sun-Times, Roger Ebert gave the film three out of four stars and praised it as "a skillful thriller", saying that Deep Blue Sea "is essentially one well-done action sequence after another [...] It doesn't linger on the special effects (some of the sharks look like cartoons), but it knows how to use timing, suspense, quick movement and [especially] surprise". He concluded that the film keeps spectators guessing in an otherwise predictable genre. In a positive review, Kenneth Turan of Los Angeles Times considered Deep Blue Sea a return to form for Harlin, especially after the "dismal swamps" of Cutthroat Island and The Long Kiss Goodnight. He described the film as "an example of how expert action filmmaking and up-to-the-minute visual effects can transcend a workmanlike script and bring excitement to conventional genre material". Similarly, Desson Howe of The Washington Post remarked that, while the film's premise feels familiar, it "knows its audience and knows what'll get them going – and even wondering". He said that Deep Blue Sea might not be Harlin's finest two hours, but he managed to build "something that, if nothing else, gives you a great big shock every few minutes". In a three-and-a-half out of four review, Robert Lasowski of The Florida Times-Union highly praised the film's pacing, intense action, and chase scenes, stating that Deep Blue Sea is "a great popcorn movie" and "what summer at the cineplex is all about".
Other reviews were less enthusiastic. Writing for The New York Times, Stephen Holden described Deep Blue Sea as "a cut-rate Titanic stripped of romance and historical resonance and fused with Jaws, shorn of mythic symbolism and without complex characters", while Barbara Shulgasser of Chicago Tribune criticized it for being an inferior imitation of Jurassic Park, but praised LL Cool J's performance and the film's realistic setting. Ian Nathan of the British magazine Empire gave the film three out of five stars and criticized its B movie conventions, stating that "You're never entirely sure whether you're laughing at or with Deep Blue Sea." Variety reviewer Robert Koehler felt the computer generated sharks were inconsistently realized, but nevertheless highlighted the flooding of the facility very positively. The dialogue between action sequences was also praised, especially LL Cool J's "blend of Bible talk, smack and wit". Despite his few lines, Jane was seen as a charismatic character and "a genuine new action star".
Deep Blue Sea was first released on DVD on December 7, 1999, courtesy of Warner Home Video. Special features include the film in a 2.35:1 anamorphic format, two behind-the-scene featurettes, five deleted scenes with extended dialogue and relationships between the characters, and an audio commentary in which Harlin and Jackson discuss the film's technical features and special effects. Warner also released the film on Blu-ray on October 12, 2010, which includes the same special features from the DVD release.
In a 2016 retrospective, Wired editor Brian Raftery considered Deep Blue Sea "the greatest non-Jaws shark movie of all time" and superior to Jaume Collet-Serra's The Shallows. He remarked that, within a genre that had been dominated by Jaws, Deep Blue Sea features "genuinely inventive" action sequences, "nicely rounded-out, human" characters, and memorable death scenes. Raftery also noted that the film was among the last of its kind, describing it as "[A]n R-rated B-movie, full of gore and chaos and smart-stupidness, but with a big-budget, big-cast sheen", in a similar way to Paul Verhoeven's Total Recall and Starship Troopers, Roland Emmerich's Stargate, and Luc Besson's The Fifth Element. Samuel L. Jackson's surprising death scene in the film appears on some lists of best film deaths of all time.
Deep Blue Sea has often been cited as one of the greatest shark films of all time. In 2012, PopMatters ranked the film third, behind Jaws and Open Water, and described it as "[O]ne of the last great [films] from action ace Renny Harlin." In 2015, Den of Geek!, a publication of Dennis Publishing, ranked Deep Blue Sea only behind Jaws and credited it for its action-packed scenes and intelligent sharks. In 2017, Slant Magazine ranked it seventh and highlighted Jackson's death scene and LL Cool J's performance, while Complex ranked it third, praising its talented actors and tight action sequences.
In 2008, Warner Premiere was planning a direct-to-video sequel to Deep Blue Sea, which would be released sometime in 2009. However, the project was never realized, nor released on the scheduled date. In June 2017, it was announced that a sequel directed by Darin Scott had begun filming in Cape Town, South Africa. The film stars Michael Beach and will be released as a television film on the SyFy Channel.