1976-77: University piano professor Mark Dalton thought he met a kindred spirit in Erica Kane. Mona Kane did whatever she could to keep them apart. Mona carried a dark secret from Mark’s past. Mark’s mother, Maureen Dalton, had been Eric Kane’s mistress. Years ago, they had child, Mark. Mark and Erica were siblings. Erica rejected Mark as a reminder of her father’s past sins.
Mark sunk himself into his work. He began giving private lessons to Devon Shepherd. Mark found himself enamored with Devon’s mother, Ellen Shepherd, even thought she was more than ten years her senior.

1978: As Mark and Ellen grew closer, Mark could not help but notice her apprehensions. Mark had proposed to her, but Ellen was hesitant to accept. Their engagement plans met another hurdle when Ellen found out Devon was pregnant. She was about to be a grandmother. Mark did not care; he loved Ellen with all his heart.
Mona called Mark frantically with the news that Erica had contracted a deadly strain of pneumonia. Mark was the first to arrive by Erica’s bedside in New York. Hovering on the brink of death, Mark comforted his newfound sister. When Erica miraculously recovered, she thanked Mark for coming to her aid. He was no longer the symbol of her father’s faults.

1979-80: No matter how much Mark loved Ellen, it was not to be. Maureen and Erica both voiced their opposition to his marriage. But, it was Ellen’s own insecurities that ended their engagement. Mark drowned himself in alcohol.
One drunken night, he met Brooke English. They began a torrid affair, but Mark made it clear that he still love Ellen. Brooke was convinced that she could make Mark love her. She moved in to his apartment, but Mark did not care for her in any other way but for sex. When Brooke became too attached, Mark kicked her out. If he did not have Ellen, he did not want anyone.

1981-82: Mark and Ellen finally married. But Ellen’s insecurities over her age made intimacy an issue. They agreed they wanted to start a family, but Ellen knew any pregnancy at her age was going to be dangerous.
Mark was refused tenure at Pine Valley University. He felt like a professional failure, but one of his students encouraged him to press on. She was Pamela Kingsley, Erica’s boyfriend Brandon Kingsley’s daughter. Mark was composing a musical that Pamela encouraged him to option. When the musical opened to great success, Mark wanted to thank Pamela. But he was overtaken by the emotions of the night and found himself in bed with her.
As Ellen continued to have issues with intimacy, Mark turned to Pamela to fill the void. But when Ellen almost found the lovers together, Mark broke off the affair. Dejected, Pamela overdosed on pills. Mark admitted everything to Ellen. Ellen asked for a temporary separation, and left Mark for New York.

1983: Mark’s separation from Ellen paid its toll on him. Erica was wound up in her own problems, so Mark felt like he had no one else to turn to. Trying to make ends meet by composing music, Mark turned to drugs for inspiration. When Ellen returned to Pine Valley, he was a daily user of cocaine.
Ellen had good news for him: she was pregnant; but, even this could not pull Mark out of his rut. The stress of the situation caused Ellen to miscarry. At the hospital, Ellen announced she was leaving Mark for good.
Mark needed money to fuel his habits. He went back to the University, but they denied him his old job. Realizing how far he had sunk, Mark tried to kick his addiction.

1984: Mark met Brooke again while she was in he process of divorcing her husband, Tom Cudahy. Mark recognized how much Brooke had grown up in the last few years. He stood by her side as she struggled with her pregnancy as a single woman. Mark was with Brooke the night she went into labor with Laura Cudahy.

1985: A municipal scandal brought Brooke and Mark together. Mark was Brooke’s primary source for her story in Tempo. A hit was put on both Brooke and Mark’s head. But, when the marksman took aim, Mike Roy swept in for the rescue. Erica ran to her fiancée as he died from the fatal gun wound. Erica lashed out at Brooke, blaming her for putting Mark and Mike in harms way. But Mark was quick to defend Brooke from his sister’s wrath. The event forced Mark to put his life into perspective. He proposed to Brooke.
Mark realized he might have jumped the gun with his proposal. Brooke was preoccupied raising Laura. Mark was offered a job as a pianist on a cruise ship. Knowing Brooke could not leave Pine Valley because of her job and her daughter; he broke off their engagement and accepted the job offer.

1986: Mark secretly made his way back to Pine Valley. He made a home for himself in Erica’s attic. He worried about anyone discovering him. His drug problem had escalated beyond his control. One night, Mark was held at gunpoint by Earl Mitchell, the husband of the woman Mark was having an affair with. Jeremy Hunter killed Earl before he could hurt Mark. In order to keep Jeremy out of prison, Mark was forced to reveal his return to all of Pine Valley.

1987: Erica led an intervention to save Mark after he was beaten up trying to score some drugs. Mark did not think he could make it through until Ellen arrived. Ellen promised to help him recover but he needed to realize he had a problem first. Mark checked into rehabilitation with Ellen by his side.
Mark got word that one of his druggy friends, Fred Parker, was dead. Fred had died of complications from HIV. Mark remembered that he and Fred had shared needles. Mark was put on a volatile cocktail of drugs until his HIV test results came in. Luckily, Mark’s test proved to be negative. The same could not be said for Mark's widow, Cindy Parker.
A familiar face back in Pine Valley surprised Mark. She was Elizabeth Carlyle, a former lover from his time in New York. Elizabeth had shocking news for Mark: Ellen’s adoptive daughter, Julie Chandler, was in fact their biological child.

1988: Mark and Ellen realized their love was still very much alive. Mark proposed marriage to Ellen again. They married in front of their family and friends. Of course, the face of Mark’s family had changed greatly since he learned Ellen’s adopted daughter, Julie, was in fact his child from a past affair.
Julie was not ready to accept Mark as her father, and began to act out. But even her juvenile attempts could not break up the happy couple.

1989: Ellen was offered a high fashion job in Hong Kong. She was hesitant to take a job so far away, but it had always been her dream. Mark promised to stand by Ellen no matter what decision she made. After a quick farewell to Erica, the Daltons were on their way to Southeast Asia.

1994: Mark returned to Pine Valley to pay his respects to Mona. She died peacefully in her sleep. Mark did his best to console Erica, but the loss was too great for her.

1995: Mark surprised his sister on what was supposed to be her wedding day to Dimitri Marick. Only, the couple had eloped the night before. Mark regaled Dimitri with stories about Erica’s love life. As a consolation, they all attended the Martin family housewarming.

2004: Jackson Montgomery called Mark in Hong Kong with devastating news. Bianca had been raped and lost her baby, and Erica had sunk into alcoholism. Mark’s arrival at Erica’s intervention was the necessary catalyst for Erica to admit to her problem. Erica also revealed the truth behind her own rape when she was only 14 years old. Their father had bartered her virginity to Richard Fields so that he would star in Eric's new movie.

2005: Mark came to Pine Valley bearing gifts for his new grandniece, Miranda Montgomery. Erica assured him that she was staying sober.