Eric and his wife, Stephanie, are co-founders of the Los Angeles-based fashion house, Forrester Creations, with Eric as its lead designer. They have five children: Ridge, Thorne, Kristen, Felicia and Angela. Two different retcons have taken away two of his children. The Angela that Eric meets in 1988 proves to be an imposter who replaced the real Angela when she died in an accident years before. In 2001 it is revealed that the biological father of his firstborn, Ridge, is billionaire shipping magnate, Massimo Marone.
Forrester Creations was first started with a $50,000 loan from Stephanie's father, John Douglas, despite his disapproval of her marriage to Eric. With Stephanie working on the business side and Eric on the creative, Forrester Creations becomes a great success, both in prestige and profits. For a time, those profits are eaten away by a far less prestigious rival, Spectra Fashions, which makes knock-off fashions all too similar to Forrester designs.
When viewers first meet Eric's wife, Stephanie, (in the second episode) their marriage is already in trouble. Eric declares the marriage "stale," while Stephanie blames their woes on his assistant, Margo Lynley, with whom she incorrectly suspects he is having an affair. Later, Stephanie inadvertently brings an actual "other woman" into his life when she makes the wrong choice of caterers for her party. One of the employees is his old college flame, Beth Henderson, now Beth Logan. After they meet, the two of them resume their love affair from thirty years before. Another employee is Beth's daughter, Brooke, who later proves an even more serious rival for Eric's affections.
Eric eventually leaves his wife for Beth, but what brings him back to the Forrester home (if not Stephanie's bed) is the revelation that he has a 24-year-old daughter he never knew: the microcephalic Angela. Stephanie had pretended she had had a stillbirth to spare Eric the pain of knowing his daughter was so severely disabled. Stephanie had hired a doctor to give Angela 'round-the-clock care in a secret house, never guessing that Angela would live until adulthood. It turns out the doctor, Todd Powell, had accidentally killed the real Angela years before. The daughter Eric meets is a perfectly functional imposter.
Other urgent matters—including the secret, withheld even from the partly amnesiac Thorne himself, that Thorne shot Ridge in the back of the head—keep Eric home for a while. And Stephanie's machinations, which bring Beth's estranged husband back in town, keep him out of that bed. But then his son, Ridge, and the publishing heiress, Caroline Spencer Forrester, discover the lies Brooke told to keep them apart and Caroline leaves Thorne for Ridge, Ridge ends his relationship with Brooke and Brooke goes after Eric to get even with Stephanie.
Eric offered comfort to a distraught and emotionally disturbed Brooke who watched Ridge, the man she loved, leave her for Caroline after she lost the baby she was carrying that was Ridge's. Eric began to pursue and support Brooke, and she eventually becomes pregnant with Eric's child. Deciding to abort the baby, she leaves town. They keep their affair quiet for quite some time. Eric was in the middle of a divorce and was fearful of what Stephanie might do. Stephanie initially learns of the relationship through Thorne, stunning Stephanie who had no idea her husband and Brooke were even involved since she had worked along with Caroline to make sure Ridge would marry Caroline. Unfortunately, her plan backfired and Eric, the man she was separated from at the time, married Brooke. Eric marries Brooke due to the pregnancy and his attempt to correct his son's harsh treatment of her. Brooke goes on to have another child by Eric after thinking it was Ridge's child due to adultery with Ridge on the floor of a lab, celebrating the invention of Belief. Eric remains very affectionate of Brooke and very protective.
In 2001, the shipping magnate, Massimo Marone, comes to town and woos Ridge's mother, Stephanie. Ridge opposes his efforts, and during a heated argument with him, cuts his hand deeply. This leads to a hospital visit and a doctor's discovery, divulged to Stephanie, that the blood types of Eric and Ridge make it impossible for them to be father and son. Stephanie reveals to Massimo that he is Ridge's father, conceived during a trip to Lake Geneva in their college days. The truth eventually comes out to both Eric and Ridge, and at first it puts an extra burden on the already strained relationship between father and son. Yet despite the efforts of Eric's real sons, Thorne and Rick—who exploit Ridge's lack of a biological tie to Eric—he continues to favor Ridge over the rest of his children.
In 2005, not long after divorcing Stephanie again, Eric returns to Brooke and they marry. The two become co-CEOs of Forrester Creations and fire Stephanie. But then Stephanie discovers a trust which her father had set up for her 40 years before, and which Eric had kept hidden, making her sole owner of the company. She takes over, fires them as CEOs but rehire them as designers, consigned to a basement office. The marriage doesn't last anyway: Brooke ends up back with Ridge, and Eric winds up back with Stephanie.
Eric's marriage to Stephanie is strained when he learns that her machinations led to an outcome she hadn't plotted: the rape of Brooke. This leads, by a circuitous route, to Eric and Brooke's sister, Donna, becoming secret lovers. Various plots by various parties pull Eric from wife to mistress and back again. Nick, who now owns Forrester, makes divorcing Stephanie a condition of selling the company back to Eric. During a Forrester fashion show, Stephanie convinces Thorne and Felicia to lock Donna in a steam room while she wears the showstopper gown, hoping to ruin the show and make Donna look responsible. Stephanie prepares a more devious plot after she is shot and discovers who shot her: Donna's brother, Storm. She conceals her knowledge from the police on the condition that Donna leave Eric. Stephanie's schemes, and the schemes made on her behalf, ultimately fail. She and Eric sign divorce papers on the May 2, 2008 episode; Eric and Donna marry on the May 9 episode.
In July 2008, Eric has a heart attack while having sex with Donna and falls into a coma. Donna has his power of attorney, thus making her acting CEO of Forrester Creations. As CEO, Donna gives promotions to Rick, Marcus Walton (her newly rediscovered son) and the mysterious Owen Knight; and she fires Ridge, Thorne and Felicia. Soon it is revealed that Eric was deliberately poisoned with potassium chloride, which was probably in the gin he drank just before his attack. Everyone is a suspect, including Owen Knight, who—out of unrequited love for Donna—confesses to the crime to take suspicion off her. But it turns out that Stephanie's sister, Pamela, poisoned Eric by giving him a potassium chloride-laced lemon bar. Her intention was only to weaken him and discredit Donna (thus avenging Stephanie) in the process.
Eric eventually recovers, but the schemes to break up his marriage continue apace. Donna gives her enemies ammunition by allowing Owen to kiss her. Just then, Eric—whom she thought was lost forever—is wheeled into the room and sees them. He eventually forgives her, but Thorne hires Donna and Owen lookalikes to make out in front of a secret camera (which a suspicious Eric himself had installed) in Owen's office. The truth eventually comes out, and Eric and Donna remain together.
At one point, Ridge thought Eric was lost forever, too. He even heard Eric's voice, begging his son to let him go. Ridge listens to this grief-induced hallucination and pulls the plug on Eric's breathing machine. After his recovery, Eric learns of this seeming treachery, which allows his younger son, Rick (who, unlike Ridge, is biologically tied to Eric), to exploit this rift. Eventually, Eric fires Ridge and appoints Rick as president of the company. Later, Eric has a change of heart and steps down as CEO so that he can give the job to Ridge. The animosity between Rick and Ridge reaches new heights when Rick accidentally crashes his car and kills his sole passenger: Ridge's daughter (by his ex-wife, Taylor), Phoebe. Rick manages to use even this situation as a means of exploiting Eric's pity. But he still is unable to get his way, which leads to him secretly stealing Forrester designs and giving them to Forrester's rival: Jackie M. Designs. Eric eventually forgives his son and resists efforts from Stephanie and others in the family to prosecute him for his crime.
Sales at Forrester are bad. The public hates the marriage between Eric and Donna. The company looks worse when Eric fires Stephanie, who ends up working at Jackie M., and still worse as Thorne and Felicia quit and Brooke takes a leave of absence. And then Pam sabotages the latest showcase by showering Donna—wearing the showstopper gown—with honey, both a reference to Brian De Palma's 1976 film, Carrie (in which the title character is showered with blood) and to Eric and Donna's well-known habit of using honey during sex play. All this—along Eric's use of illegal immigrants as employees—gives the publishing tycoon, Bill Spencer, Jr. (the retcon-created son of the Bill Spencer, a character who mainly appeared from 1987 to 1994), the chance to take over the company. Bill's various efforts fail, until the Forresters are 30 minutes late on their bank loan. Bill pressures the banker to foreclose and sell him the company. The Forresters are furious, but Eric vows to win the company back. Yet it is Ridge's daughter, Steffy, who is able to blackmail Bill into selling the company back to the clan. Eric, Stephanie, Ridge and Taylor (Steffy's mother) end up as equal co-owners of the company.
Eric objects when Donna hosts a talk show called The Catwalk, which is owned by Spencer Publications. Especially objectionable is how close this brings her to the Spencer employee, Justin Barber, Donna's ex-boyfriend and the father of her son, Marcus. Their marriage is further strained after Stephanie inadvertently causes Donna's mother, Beth, to drown in the Forrester swimming pool. Donna wants to press charges, and Eric refuses to let her. Donna realizes how strong the ties are between Eric and his ex-wife; and this realization leads to their divorce. When Stephanie proves to have stage-four cancer, Eric's love for her bubbles to the surface, and the two reunite.
Ridge's son, Thomas (by Taylor), wants to make his mark on the fashion industry with a new line called Taboo, which he promotes via scandal: he surprises Brooke on the runway with a kiss. His purpose is to exploit the public's fascination with his stepmother's pseudo-incestuous romances (with Ridge, Nick, Thorne and Eric), but Taylor worries that Thomas is genuinely attracted to Brooke. Eric supports the line, which leads to a clash with Ridge, who vehemently objects to it. At one point, Eric confesses to Ridge that he feels Taboo is payback: Thomas is doing to his father what Ridge did to his. Eric however, discounts the fact that Brooke was first Ridge's sweetheart, fiancée and almost the mother of his children after she had three miscarriages and fails to see that he shouldn't have dated one of his son's ex-fiancées, let alone marry her.
The relationship between Eric and Stephanie falls into crisis when Eric asks his partner to have a physical approach because he feels a lack of affection, but Stephanie refuses because the cancer makes her feel unattractive. Eric moves closer again Jackie and with her he shares much kisses. Ridge finds out what's going on between Eric and Jackie and he warns his father to finish anything not to hurt again Stephanie. Eric decide to respect Stephanie's choice and he back with her. The two find again their happiness.
On March 9, 2012 Eric and Stephanie remarry in the presence of Gladys Pope. In October 2012, Doctor Lewis told Stephanie that her lung cancer has returned. Despite the desperate pleas of her family and friends, Stephanie refused to accept treatment; she decided instead that she would like to enjoy her final days so Eric planned an Irish-themed party in her honor at the mansion. On November 26, 2012, Stephanie lost her battle with cancer lakeside at the Big Bear cabin.
After Stephanie's death, Eric feels alone and falls into a deep despair. Every evening, in fact Eric prepares two martinis and talk to the dead wife, and orders him to go ahead. The man can not stop looking for Stephanie everywhere: even though he left it many times in the past, she has never left him, so he had come to think that there would always have been and now does not know how to be able to accept that there is more. His family stands beside him, urging the man to focus on work. Eric discovers the existence of a change to the testament of Stephanie, the woman did not allow the company's future was in the hands of Thomas, so he spent his shares to Eric, that regaining control also legal, as well as patriarchal, trying to appease the feud between Thomas and Rick, finally deciding who is the worthy successor to Ridge through a fashion challenge judged by the same Eric. The latter chooses as the winner of his son Rick, sparking anger and disappointment in Thomas, elements that led him to decide to move to Paris. Although it is back to being at the head of Forrester, Eric, however, continues to feel the lack of his wife.
Eric finds himself surrounded by the love of three women, Pam, who shares her grief over the loss of her sister, Donna, who stands beside him and comforted him, and finally Taylor, who finds himself betrayed by Stephanie (the woman has asked the proximity of Brooke and not her) and once again frustrated by Brooke's children: on the one hand, there is Steffy that Liam pregnant, must wait for the choice of the latter and on the other that Thomas wants to go in Paris. Eric begins to collect Taylor's confidences and he decides to help her. In fact, Eric offers convinces Thomas to stay in Los Angeles by appointing him vice-president of Forrester Creations. Taylor is grateful to Eric and kisses him. The two spend much time together, getting closer and closer and sharing more kisses. Eric confides to Taylor the lack of intimacy between him and Stephanie, so Taylor promises to wear lingerie for him. Eric is happy again and feels not having to answer to anyone: in the past had already courted Taylor, but then he had always ignored the attraction because of Stephanie. But now Eric and Taylor feel of not having to brake to Stephanie saying that to go on is what the woman would want for them. During a romantic dinner, Taylor wearing lingerie for Eric, but they are interrupted by Brooke, appalled, he discovers their relationship and accusing Taylor of using her new-found power to have influence over Eric's decisions at Forrester. That same evening, Eric and Taylor declare their feelings, then they make love for the first time. When Taylor moves into the Forrester mansion, Brooke is determined to stop her. Eric and Taylor are happy together and Eric publicly announces his love for Taylor stating that he finally found happiness after Stephanie's death. The problems arrive when Brooke asks Eric a sacrifice: she confesses to him that she's expecting Bill Spencer's child, her sister Katie's husband, and asks Eric to pretend to be the father because she doesn't want to create another scandal, but Eric refuses because he has a committed relationship with Taylor and he doesn't want to ruin their happiness. Brooke, however, did not give up and say they want Eric back into her life. When Brooke suffers a miscarriage, she pleads with both Eric and Donna to keep it a secret from Katie, who both agree to do so. But Taylor finds out Brooke's secrets and, at Brooke's birthday party, she blurts out that Brooke had an affair with Bill. Eric and Taylor hit a snag in their blissful relationship over his keeping Brooke's secrets.
Thanks to the agreement between the Quinn Artisan Jewelers and Forrester Creations, Eric makes the acquaintance of Quinn Fuller with whom he begins a brief romance with.
Eric welcomes his niece Ivy (Ashleigh Brewer), daughter of his brother John (Fred Willard) to Los Angeles and she and Quinn corroborate on a jewelry line.
Eric decides to appoint Ridge CEO, but the discovery of a clandestine kiss between Caroline and Ridge leads him to appoint Rick. After Rick behaves horribly as CEO and Eric refuses to remove him, Ridge, Liam and Steffy use their stock to take over the company. Ridge is CEO, Steffy is President and Bill's son, Liam, is Vice-President.
For his portrayal of Eric, McCook was nominated for a Daytime Emmy Award in 2001 and 2012.