[[quoteright:300:https://static.tvtropes.org/pmwiki/pub/images/sea_of_love.jpg]]

A 1989 Neo-Noir thriller (with some comic elements) directed by Harold Becker, starring Creator/AlPacino, Creator/EllenBarkin and Creator/JohnGoodman.

The film follows unhappily-divorced [[UsefulNotes/NewYorkCityCops NYPD]] Detective Frank Keller (Pacino), who finds himself investigating the death of a man who'd placed a rhyming poem personal ad in a lonely hearts column. When more victims turn up under the same circumstances, Frank and Detective Sherman Touhey (Goodman) end up investigating the case, coming to suspect a woman who'd answered the ad, based on a lipstick-smeared cigarette. They place an advertisement of their own (using a rhyming poem that Frank's mother wrote for his father), with Frank meeting the women for the dates, and Sherman collecting their fingerprints from wine glasses while disguised as a waiter. One woman, Helen Cruger (Barkin), ends the date early without leaving fingerprints. As Frank attempts to follow her for a second date, he finds himself in danger of falling in love, even as he wonders if she may be the killer.

[[TitledAfterTheSong The movie's title comes from the main song in its soundtrack]].

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!! Tropes:
* TheAlcoholic: Frank, in a DrowningMySorrows way.
* BigFun: Sherman, a jocular, helpful guy who also has elements of the {{Sidekick}} and PluckyComicRelief, but still a smooth detective who contributes well to the case himself.
* CluelessMystery: In his [[https://www.rogerebert.com/reviews/sea-of-love-1989 review]], Creator/RogerEbert criticized the film for this. The killer is [[spoiler:Helen's crazed ex-husband Terry, a.k.a. the cable guy who appears in two brief scenes]]. The only clue to this is Helen mentioning offhandedly that [[spoiler:she's divorced]], but even then there's no prior indication that [[spoiler:Terry is her ex-husband]] at all.
* ComicallyMissingThePoint: When Frank runs into someone he knows on the case (while he's taking a turn posing as the waiter and letting Sherman have the dates) she recognizes him as a policeman and asks if he lost his job.
* CrazyJealousGuy: [[spoiler: The killer is Helen's ex-husband Terry, murdering any man she goes on a date and sleeps with]].
* CriminallyAttractive: Frank's knowledge that Helen might be a murderer can't overcome his feelings for her. [[spoiler: She didn't do it though]].
* DaChief: Creator/JohnSpencer plays Frank's precinct captain, a no-nonsense, but fairly reasonable man who is skeptical about the plans cost and results, but is willing to try it out.
* TheDogWasTheMastermind: [[spoiler:Terry -- the cable guy who appears in two brief scenes -- is the killer]].
* EverybodyLaughsEnding: Downplayed but the ending has [[spoiler: Frank and Helen smiling a little as he successfully tries to reconnect with her]].
* GlamorousSingleMother: Helen is divorced, dates a lot, and has a young daughter.
* HardBoiledDetective: Frank is a somewhat unhinged, lonely man who sometimes loses his temper.
* InLoveWithTheMark: A heroic version when Frank falls hard for Helen even as he's investigating her.
* InVinoVeritas: While on one date with Helen, Frank drunkenly admits that he met her on a sting operation for the police department. When he sobers up, he claims that this was a lie meant to drive her away because he'd been about to try and commit to a relationship and then gotten cold feet.
* InnocentlyInsensitive: One (older) woman is hurt after her date with Frank when she lingers around long enough to see other people having dinner with him that same evening as part of the investigation.
* LuredIntoATrap: The HardBoiledDetective hero and most of his coworkers are introduced tricking several wanted crooks into thinking they won a contest to meet the New York Yankees at a luncheon. The Yankees don’t make an appearance at the venue, but lots of guns and handcuffs do.
* TheMissusAndTheEx: While Frank's ex-wife never appears in the movie, her current husband is one of the other detectives on the case and has a tense, but professional relationship with Frank (aside from one blow-up early on).
* MyGreatestFailure: Sherman and Frank are upset when one man who put in a lonely heart poem who they interview is murdered the next day, agreeing that they should have followed him.
* NiceToTheWaiter: Frank tries to be polite towards and interested in people like the doorman at the first victims apartment, noting that it makes them feel more cooperative.
* OneDialogueTwoConversations: Near the end [[spoiler: When Frank thinks Helen is the killer due to her having dated and/or slept with all of the murdered men, he threatens her and drives her off. Frank thinks he's preventing her from killing him, while Helen thinks that Frank is unhinged]].
* PetTheDog: After the UndercoverCopReveal below, when one criminal arrives late, accompanied by his young son, after checking his name on their list and finding out he's wanted for a relatively minor crime, Frank and his colleagues tell the man that he arrived too late to be admitted and send him away rather than arrest him in front of his kid.
* SerialKiller: Frank and Sherman are investigating the shooting deaths of three men who placed ads in the Lonely Hearts column of a local newspaper, suspecting that a female serial killer answered the ads and killed the men. It turns out that [[spoiler:Helen did indeed sleep with all three men, but it was her jealous ex-husband Terry who killed them]].
* TwoAliasesOneCharacter: [[spoiler: Terry is both Helen's ex-husband and a cable guy who was near the scene of one murder]].
* UndercoverCopReveal: Frank is introduced hosting a party, supposedly for randomly selected contest winners to meet the New York Yankees. It turns out those "contest winners" are all wanted fugitives who were tricked into arriving and who the police all arrest (something based on a real-life story).
* WorkingTheSameCase: Frank and Sherman investigate separate killings by the BigBad at the beginning of the movie. Unlike most cases of JurisdictionFriction they become fast friends and quickly join forces to investigate together.
* YouNeedToGetLaid: Frank's boss feels this way, insinuating that the sting operation is just Frank's way of getting some free dates and offering to set Frank up with his sister-in-law.
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