Dominick "Nick" Marone was raised by his mother, Jackie Payne, and grew up thinking Frank Payne was his father. Nick became a sea captain for Marone Industries and was injured when his tanker ran aground. But Nick soon learned that his boss, Massimo Marone, was really his father, and that he had a half-brother in Forrester Creations' heir apparent Ridge Forrester. Nick clashed with Ridge when he took a desk job at Marone Industries and an interest in Ridge's on-again-off-again love, Brooke Logan. Despite Nick's attempts to woo her, Brooke married Ridge, who went missing on their honeymoon in South America; Nick aided in the search and found Ridge had been kidnapped by Forrester family foe Sheila Carter. Nick's rescue attempt ended with him captured by Sheila, and, in the confusion over Massimo and Brooke trying to apprehend Sheila, Ridge fell into a furnace and was presumed dead. Nick comforted Brooke, which turned into lovemaking.

Though Ridge turned up alive, Brooke turned up pregnant, and a paternity test named Nick as the father. Nick proposed to Brooke, but on the day of their wedding, Nick and Massimo were arrested for paying off government officials based on files Ridge found on Nick's computer; Nick was released for lack of proof. Nick was overjoyed when Brooke gave birth to a son, but Jackie soon revealed that she'd learned his paternity test had been fixed and that she'd kept quiet about it. Nick was furious with his mother and let Brooke go after a new test confirmed that Ridge had fathered Brooke's baby.

Nick bonded with Ridge's mother, Stephanie Forrester, who shared Nick's disappointment that Ridge had reunited with Brooke. Nick dated Stephanie's daughter, Felicia Forrester, and researched a mysterious bottle of pills that had fallen out of Felicia's purse. Nick and Felicia grew close when she admitted having colon cancer; they made love, but Felicia moved to Europe after her cancer went into remission. Nick began spending time with Brooke's daughter, Bridget Forrester, a doctor who had cared for him after his tanker accident; Nick realized he had feelings for Bridget after he rescued her and Ridge from a mine shaft. Nick asked Bridget to marry him; their wedding was halted when Ridge thought he saw his deceased wife, Taylor Hayes, lurking outside. Nick helped Ridge dig up Taylor's grave, finding a wax dummy inside; Taylor was indeed alive.

Nick lent Brooke a shoulder after Stephanie had a heart attack and announced that her dying wish was to have Ridge remarry Taylor; Nick and Bridget hit a rough patch when she overheard him confessing that Brooke was the most important thing in life to him. Nick briefly battled Dante Damiano for Bridget's affections, but when Nick and Bridget made it to the altar again, that ceremony was halted by Jackie's news that Stephanie had faked her heart attack to get Ridge away from Brooke. Nick felt further drawn to Brooke after he saved her young daughter, Hope Logan, from drowning in a Jacuzzi. After Nick found out that Bridget aborted their baby, Nick wanted to recommit to Brooke until Bridget revealed she'd lied about the abortion to test Nick's loyalties. Nick and Bridget finally tied the knot, but Nick pined for Brooke to the point he experienced hallucinations.

Nick kissed Brooke, not knowing Stephanie was watching; after Bridget walked out on him, Nick's dreams of being with Brooke were dashed when she announced she had remarried her ex-husband, Eric Forrester. Nick and Bridget found their way back to each other; just as Bridget started having problems with her pregnancy, Nick discovered he had a son with Felicia, who had come back to town. When it seemed Felicia was dying from her returning cancer, Nick and Bridget offered to raise Felicia's boy, whom she'd named Dominick after Nick. Nick lost two children when it turned out Dante was Dominick's father, and when Bridget miscarried Nick's child.

After Bridget set Nick free, he hoped to reunite with Brooke, but she was set on remarrying Ridge; Nick got drunk with Taylor, though they didn't act on their attraction. Ultimately, Nick finally got to be with Brooke, though they held off on making love until his divorce from Bridget became final.

When Nick discovered that Massimo had Jackie arrested on false charges so she'd help keep Nick and Brooke apart, Nick disowned Massimo and forced him out of Marone Industries. Later, Nick punched Ridge for making love to Brooke while she was under the influence of antianxiety medication. Nick was set to exchange vows with Brooke at a seaside wedding until he saw nude photos of her plastered on billboards; Stephanie, who temporarily wanted Brooke back with Ridge, had used Brooke's discarded promo pictures to discourage Nick. After Nick married Brooke anyway, Brooke's sister, Donna Logan, told Nick she'd seen Brooke kissing Ridge; a hurt Nick slept with Bridget and got her pregnant. Nick was thrown overboard from his boat, The Shady Marlin, by a furious Brooke, though it turned out Bridget was pregnant by Dante, not Nick.

Nick went on the warpath after Donna witnessed Stephanie pushing Jackie over a second-story railing at the Forrester mansion; Nick retaliated by holding Stephanie over the same railing and threatening to put Stephanie in jail if Eric didn't sign control of Forrester Creations to him. Nick installed Jackie as president and Donna as lead model, his actions costing him his marriage to Brooke. To deal with his anger, Nick began sessions with Taylor, a psychiatrist, and had a memory of Jackie accepting money for sex; Nick felt disillusioned as Jackie tearfully admitted turning tricks to keep her young son fed. Nick raged when Stephanie made Jackie's prostitution public and actively worked to undermine Forrester Originals, the company Brooke, Ridge, and the other Forresters had formed after Nick's takeover of Forrester Creations.

Nick pursued Taylor despite her engagement to Ridge's brother, Thorne Forrester. Once Taylor and Thorne split up, Nick chose Taylor over a reconciliatory Brooke and proposed. After Nick and Taylor married, Nick was arrested for the murder of Shane McGrath, whose body was found on Nick's boat. Nick suspected he was being framed and confronted Stephanie, not knowing she'd filed a restraining order against him, the violation of which landed Nick in jail again. As Nick was about to be convicted for killing Shane, Ridge stepped forward and admitted that Shane had committed suicide in front of him; Ridge had panicked and used Nick's boat to get rid of Shane's body. A free man, Nick and Taylor decided to have a baby via in vitro fertilization.

Cigar smoker Nick left his lighter behind while visiting Hope and her little brother, R.J.; the kids found the lighter and set fire to the living room, prompting Child Protective Services to remove them from Brooke's home. Later, Nick sold Forrester Creations back to Eric on the condition that Eric divorce Stephanie, then bought competitor Spectra Fashions for Jackie, renaming it Jackie M. Taylor gave birth to Nick's son, but Nick soon learned that there had been a mix-up in the lab and that their egg donor was Brooke. Nick couldn't comfort Taylor, even after her long-time rival donated bone marrow to help heal the baby's immune deficiency. Meanwhile, Nick became a suspect in the shooting of Stephanie, who had inadvertently caused Brooke to be raped; Nick had threatened Stephanie's life, but the shooter turned out to be Brooke's brother, Storm Logan.

With his son, Jack, being Brooke's biological child, Nick confessed to Taylor that he was still in love with Brooke, triggering a nasty court fight that ended with Nick obtaining sole custody of the boy. Nick and Brooke were on the verge of reuniting until she decided to stay with Ridge; soon Nick found his way back to Bridget, but was intrigued by Brooke's other sister, Katie Logan, who was Jack's babysitter. Nick was confused about his feelings for the three Logan ladies but gravitated toward Bridget, who moved in with Nick just as Storm accidentally shot Katie. After Katie needed a heart transplant and Storm shot himself to donate his own heart, Nick spent time with Katie at Bridget's behest, knowing Katie had developed a crush on him. As Katie's body rejected Storm's heart, Nick helped Bridget throw Katie the prom she never had, then took Katie sailing to Catalina Island.

Nick located Katie's mother, Beth Logan, who had been conspicuously absent during Katie's health crisis; Nick learned that Beth was suffering from the onset of Alzheimer's disease. After Bridget healed Katie with an experimental cure, Nick married Bridget with Katie officiating the ceremony, but soon learned Katie was pregnant and sheepishly admitted to Bridget that he had made love to Katie on Catalina as Katie's dying wish. Nick proposed to Katie after Bridget walked out on him. Later, Nick lost another child when Katie miscarried, and when Jackie and Bridget arrived to protest Nick's wedding to Katie, Nick found himself single again because Katie thought better of going through with the ceremony.

Amid Jackie M's financial problems, Nick was surprised when Brooke's son, Rick Forrester, who was feuding with Ridge, offered Nick stolen Forrester designs in exchange for a presidency at Jackie M. Nick and Rick's deal fell through, though Nick was amused when "Madame X," the new designer Jackie hired, turned out to be Bridget. Nick caught a break when Stephanie, who had defected from Forrester, offered to invest money in Jackie M; Nick gave his former enemy a job and threw a pep rally for Stephanie when she had trouble bouncing back from a mini-stroke.

Nick was jealous when Bridget dated model Owen Knight, but soon Nick and Bridget found their way back to each other and remarried. While honeymooning in Hawaii, Nick expressed his disapproval upon seeing Jackie marrying Owen herself. Given Bridget's history of miscarriages, Nick suggested they use a surrogate when Bridget wanted to try for another child; Nick and Bridget hired Sandy Sommers, whom Nick soon found out was really Agnes Jones, a rape victim hiding under an assumed name. Nick promised to keep Agnes' secret from Bridget and tracked down Agnes' rapist, Graham Darros, tricking Graham into chewing a piece of gum to get a DNA sample from him. Nick stopped Graham from raping a grown-up Hope, but ran afoul of Bridget, who was furious Nick had kept the truth about Agnes from her.

Nick refereed between his feuding wife and surrogate, but when Bridget and Agnes argued on the staircase, Agnes fell and lost Nick's baby. Nick and Bridget made up and celebrated Bridget's own surprising pregnancy, but Nick was furious when Agnes reported hearing about the grief sex Bridget had with Owen the night of Agnes' miscarriage. Nick punched Owen and divorced Bridget, but not before humiliating her by announcing her betrayal to the entire Jackie M staff. Nick moved on with Agnes and hired former Forrester designer Amber Moore to replace Bridget, though Nick wasn't satisfied with the quality of Amber's work. Nick fired Amber upon discovering that her suddenly improved designs were stolen from Forrester.

Long-time smoker Nick had a non-cancerous spot removed from his lung and agreed to give up his cigars after Stephanie, Jackie, Agnes, and Owen staged an intervention for him attended by several cancer survivors. When Brooke and her stepson, Thomas Forrester, went missing at sea after a plane crash, seaman Nick aided in their rescue efforts. Nick became a bachelor again after his lukewarm relationship with Agnes fizzled out.

Nick let Katie stay on the Marlin after she had a fight with her new husband, Bill Spencer, Jr.; Nick found Bill's fist in his face when Bill saw Katie with Nick. Further financial troubles at Jackie M forced Nick to move Jackie and Owen in with him, which cramped his style. Nick balked when Bill, who wanted to crush Forrester Creations, offered to buy Jackie M; Nick came around to selling but changed his mind when Jackie decided she'd rather fail on her own than give up the company to a conglomerate.

Nick discouraged a seduction attempt from Stephanie's recently single sister, Pam Douglas. When Jackie wanted Nick to play on Pam's affections to get Pam to steal Forrester designs, Nick refused at first but ultimately found Pam interesting, kissing her passionately when Pam delivered the first sketch. Nick aroused Pam's jealousy when he also kissed her frenemy, Donna, and gave Donna a place to stay on his boat. But Nick had far more to worry about when Bridget recognized Eric's designs on Jackie M's runway and blew the whistle. Though Nick denied stealing the sketches, Donna figured it out when she saw Nick and Pam dressed up as sea creatures on Let's Make A Deal. Nick appeased Donna's disillusionment by admitting he had fallen in love with her, but soon after, Nick, Jackie, and Owen disappeared from the canvas without explanation; it was later mentioned that Nick had sailed off to ports unknown on the Shady Marlin II. Nick's son, Jack, is presumably with him.

In 2022, Nick appeared to Brooke in a dream for the show's 35th anniversary, reminiscing about their relationship as a way to remind Brooke of her value owing to problems she was having with Ridge. Dream Nick did not mention his son with Brooke/Taylor, Jack.