November 2017 to present [contract]

Justin Barber is the son of Wesley Barber and Valerie Lowell, and is related to the Barbers of Genoa City, Wisconsin. An executive at Spencer Publications, Bill Spencer, Jr. brought Justin out from New York to work alongside him in Spencer's home office in Los Angeles. Justin's main assignment was to aid in Bill's takeover of design house Forrester Creations.

Justin ran into Donna Logan, whom he'd dated in high school, and wanted to know why Donna had suddenly broken things off and moved to Europe. When Justin saw Marcus Walton with Donna, Justin did research and discovered that Donna had just reconnected with Marcus, the son she'd given up for adoption. Justin confirmed Marcus was his and got to know him, even though Marcus had been legally adopted by Donna's husband, Eric Forrester. Justin cast Donna as the co-host of Bill's fashion talk show, The Catwalk; when Donna divorced Eric, Justin was instrumental in convincing Donna to ask for half of Eric's 25% share in Forrester, which Donna then sold to Bill.

Justin got his hands on a video tribute being made for Donna's sister, Forrester executive Brooke Logan, and a recording exposing how Brooke mistakenly slept with her daughter's boyfriend. Justin added the audio and leaked the video to the world in hopes of aiding Bill's crusade against Forrester, but Justin barely kept his job after Bill objected to his actions because Brooke was also the sister of Bill's wife, Katie Logan.

Justin romanced Donna, marrying her with Justin's Genoa City cousin, Olivia Barber Winters, in attendance; Justin hoped Marcus would take his last name as well. Justin inexplicably kissed Malaika Maponya, a doctor he'd known in South Africa, and was distant when Donna almost caught them. Months later, Justin and Donna realized they'd only gotten married so Marcus could have his parents together, and amicably divorced.

Justin continued aiding Bill in his schemes against Hope Logan, whom Bill didn't think was good enough for his son, Liam Spencer; Justin leaked news of Steffy's engagement to Liam so Hope would see it and helped spring Hope's father, Deacon Sharpe, from jail to prevent Hope's own wedding to Liam. Justin was nearly discovered when he accidentally "pocket dialed" Marcus, who overheard Justin and Bill discussing their plots. Justin dug up dirt on the wrongly convicted Maya Avant to keep her away from Rick Forrester, who was dating Bill's niece, Caroline Spencer. Then, after Katie divorced Bill for having an affair with Brooke, Justin approved Katie's request for 1% of Spencer Publications, inadvertently allowing Katie to become CEO after Katie made Bill's sister, Karen Spencer, the majority stockholder. Justin presented Katie with papers that would return control to Bill, which Bill seduced Katie into signing; Justin was shocked when Brooke replaced the papers with a pile of leaves.

Justin uncovered photos of Brooke's longtime love, Ridge Forrester, at a gay pride parade to help Bill keep Brooke from reuniting with Ridge. Justin accompanied Bill to Abu Dhabi, where Bill was set to marry Brooke until Ridge showed up to stop the ceremony; on Bill's orders, Justin banked the helicopter Ridge had dragged Brooke onto, plunging Ridge into the Persian Gulf. Justin was relieved when Ridge turned up alive with no memory of the event. Tasked with flying Bill and Brooke to a second wedding on Catalina Island, Justin was punched by Ridge, who remembered Abu Dhabi and took over Justin's helicopter. Justin was grateful Ridge chose not to press charges.

Justin ran an exposé on the transgender Maya to help Bill oust her boyfriend, Rick Forrester, who had become the tyrannical CEO of Forrester Creations. Later, when both Liam and his nemesis, Quinn Fuller, went missing, Justin located Quinn's ex-husband, Deacon, and pumped him for information about Quinn. After Liam returned reporting he'd been held by Quinn while suffering from amnesia, Justin advised Liam to drop the case as Liam and Quinn had lived as man and wife, which would make it very difficult to make any charges stick. Justin also arranged a settlement in Bill's second divorce from Katie, working to expedite the process by helping Bill establish residency in Nevada.

When Bill again attempted to marry Brooke, Justin attended the wedding and reconnected with Donna, but shared his fellow guests' shock when Bill, who was upset that Ridge had tried to sway Brooke's affections before the ceremony, left Brooke at the altar.

Several months later, knowing Bill wanted to bulldoze struggling design house Spectra Fashions to make way for a skyscraper, Justin suggested that Bill capitalize on a small electrical fire that broke out at the company and made arrangements to burn Spectra to the ground. Justin pledged his loyalty to Liam when Liam recorded Bill's confession and used it to take over as CEO, but Justin continued reporting back to Bill and helped Bill's other grown son, Wyatt Fuller Spencer, discover that Liam had bought the burned-out Spectra building and given it to young designer Sally Spectra.

Justin stole a flash drive with Bill's confession on it and was on hand when Liam lost his CEO seat to Bill, who had hired a hacker to delete the recording. On board with the destruction of Spectra, Justin was tasked with making sure Liam and the Spectras, who had staged a sit-in, had exited the building. However, Justin missed seeing Liam and Sally re-entering the structure and was unable to stop Bill from blowing up Spectra with Liam and Sally inside. Later, Justin agreed to arrange a romantic getaway for Bill but was unable to pull the identity of his mystery woman out of him.

Knowing Bill was planning to disinherit Liam and Wyatt and kick them out of the company, Justin appointed himself temporary CEO when Bill was hospitalized from being shot in the back; Justin scoffed at the idea of providing proof to Wyatt and was briefly a suspect in Bill's shooting. After Bill recovered, Justin seemed to have a change of heart and only reluctantly set up a seduction scene on Bill's orders to make Wyatt think Bill was still romancing Liam's wife, Steffy Forrester, so Wyatt would tell Liam and free Steffy up for Bill. Justin argued with Bill over the deception, causing Wyatt to overhear. Justin felt it wasn't Bill's place to push Liam back toward Hope so Bill could have Steffy for himself.

Justin was thrilled to greet his niece, Emma Barber, who was enjoying an internship at Forrester Creations. Justin advised Emma not to let the Forresters know she was a Barber, fearing his connection to Bill and the Forresters' animosity towards him would jeopardize Emma's opportunity; Justin ultimately ended up defending Emma when she was caught taking photos of exclusive designs. Later, on Bill's orders, Justin snapped his own photo of Liam and Hope in an embrace for Bill to use in his campaign to win Steffy.

After Bill's pursuit of Steffy led him to neglect his youngest son, Will, Justin represented Bill when Katie filed for sole custody of the boy. Justin kept his ears open and got a lead that Ridge had visited the judge before the hearing; Justin helped Bill secretly record Ridge and the judge discussing Ridge's influence over him. But Justin was shocked when Bill claimed he was a changed man and let Ridge off with a slap on the hand. Justin had a feeling Bill was doing it all to win back Brooke, in whom Bill had a developed a renewed interest.

Seeing that Bill was becoming closer to ex-wife Katie as they co-parented Will, Justin convinced the returning Donna that they should work together to reunite Bill and Katie. Justin played dumb when Bill and Katie kept finding themselves set up in romantic situations, but it turned out Will was making those arrangements with his father's credit card.

Justin was devastated when Emma died in a car accident and expressed his gratitude to Forrester Creations for holding a memorial for the girl. Justin assumed Emma had been texting while driving when the police found a half-composed message to Hope on Emma's phone at the crash site.

In 2021, Justin found himself crafting a defense for Bill and Liam, who had both been jailed for covering up a hit-and-run involving Vinny Walker, the best friend of Ridge's son, Thomas Forrester. When Thomas produced video evidence that Vinny had thrown himself in front of Liam's car on purpose to frame Liam, Justin punched Thomas and dragged him into a makeshift cage -- it turned out Justin had become resentful of Bill's treatment of him and refusal to promote him, so Justin had determined to seize control of Spencer Publications in Bill's absence. Justin needed Bill to stay in jail for his plan to work, but knew he couldn't keep Thomas and his evidence captive forever. Losing his nerve after Hope caught Justin with Thomas' phone, Justin decided to free Thomas but discovered that Hope had already broken Thomas out of the cage with a crowbar. Justin anonymously sent Thomas' phone to the police so Thomas could present his evidence, which freed Liam and Bill, but Justin was shunned by Bill after his former best friend learned what he had done. Justin went to Ridge and tried to ally with him to stay out of jail himself, offering to work with Ridge against Bill, but Ridge didn't bite.

Justin got a chance to make things up to Ridge when Ridge tasked Justin with following Quinn, whom Ridge suspected was cheating on husband Eric with Justin's adoptive nephew, Carter Walton. Justin caught Quinn and Carter in bed and was hard pressed to believe that Eric had sanctioned the extramarital activity because Eric was struggling with erectile dysfunction. Although Carter and Quinn begged Justin not to report back to Ridge, Justin felt an obligation to and did just that.

Justin disappeared from the canvas for three years, until 2024, when he resurfaced as an attendee at the comeback concert of formerly homeless rocker Tom Starr. Justin witnessed Tom falling dead after his set, then later ran into Bill; it was said that Justin and Bill had resolved their issues off-screen. Justin seemed uncomfortable when Bill remarked about Tom's co-worker Paul "Hollis" Hollister also dying suddenly at the same venue.