Luis is the second eldest of five children. A superstar in high-school (captain of the football, baseball, and basketball team, class president and valedictorian, and a major ladies man), Luis had dreams of being a lawyer, but his father's disappearance when he was a young child left him in the care of his older brother Antonio, and when Antonio left town after Luis graduated high-school, it meant he had to stay home, get a job, and support his mother and siblings. He even broke off his relationship with Beth Wallace, his high-school sweetheart and his first love, because he was afraid he would leave her like his father left his mother.

He first met Sheridan Crane when she crashed into his police car (twice!), and sparks continued to fly when it turned out that her community service was to be played out at the community center where he was youth director. They had a couple of uneventful dates, but nothing really came of it, and she started dating his best friend, Hank Bennett, with Luis' blessing. Luis began dating Beth again briefly, but was too into Sheridan to be as into rekindling their old love as Beth was. She slowly faded out of the picture.

Sheridan and Luis continued to dance around each other until Luis was assigned by the FBI to be Sheridan's bodyguard. They kept getting closer and closer, until they finally admitted their feelings to each other. Unfortunately, Sheridan was shot shortly after. Devastated by her death, Luis was inconsolable...until it turned out she was actually alive. After recovering in the hospital, Luis and Sheridan reaffirmed their love for each other, and Luis gave his blessing to Theresa and Ethan's engagement.

After a LOT of false starts, they finally managed to make love shortly after Ethan was revealed to be Sam Bennett's son. They're making tentative plans for the future...starting with their engagement! Unfortunately, the double-wedding didn't go off as planned...and now, Sheridan is presumed dead. In the months since Sheridan died, Luis has begun a downward spiral, and Hank finally set him up with Beth, knowing how much they once loved each other, believing it's time his friend stops looking for Sheridan around every corner. During this time, Luis also discovered that his brother is alive and well, but will not come home.

Luis finally accepted that Sheridan was gone, even though he searched daily for any news of her, which included looking up their past lives on the Titanic. He began to move on with Beth, and the two had just become engaged when a miracle happened, and Sheridan was back in Harmony...only she was engaged to his brother, Antonio! The two carried on their relationship in secret once it was learned that Antonio had a life-threatening illness. Luis finally gave Sheridan an ultimatum...either she break up with Antonio, or he was going to move on. Sheridan chose Antonio, and out of pique, Luis asked Beth to marry him. He and Sheridan were going to elope the night before the wedding, but missed each other at the judge's office.

On the day of the wedding, Beth's mother collapsed in the aisle, and while Antonio and Sheridan did get married, Luis and Beth did not. When the two couples happened to check into the same honeymoon hotel, Luis and Sheridan met in the hallway, and cleared up the confusion about the elopement. Unfortunately, Sheridan had neglected to give Antonio his medication that night, and he ended up needing to be hospitalized. When Luis admitted that he would rather see Antonio dead than on an experimental drug (knowing that with Antonio dead, Sheridan would be his), Pilar slapped her son across the face, but soon begged for forgiveness.

Luis continued to pine after Sheridan, and when he learned that Sheridan was pregnant, he was thrilled...until he realized that his brother could be the father. Shortly after that, Beth announced to him that she was pregnant as well. Luis and Sheridan decided that they would raise her child and Beth's child together, with no interference from Beth or Antonio. Luis has grown to think of Sheridan's child as belonging to him, even though there is a very real possibility that Antonio is the father. Things took a turn when Sheridan was kidnapped. Antonio and Luis searched frantically for weeks, and finally found her. Luis was determined to find her child as well, but soon accepted that the child was dead, even though Sheridan just couldn't believe it.

Once Sheridan returned home, she continued her marriage to Antonio and insisted to Luis that she wanted to be with her husband. Luis could not accept that, and continued to pursue Sheridan, which ultimately led to the events that resulted in Antonio's death. Sheridan and Luis were finally free to be together, but Luis' refusal to believe that Marty was Sheridan's son and not Beth's continued to drive a wedge between them. DNA tests finally proved that Marty was their child, but Beth managed to leave town with the boy and Sheridan could not forgive Luis for not believing her. Luis left town to find Beth and Marty, and a few months later, his family was informed he was dead.

Luis turned up alive and well in Otto Krause's home in Hawaii, and once he began to recover in the hospital he asked Sheridan to marry him, not knowing that she was already married to Chris, the man who had saved his life. Luis became determined to win her back, even though she made it clear to him that she was going to stay with Chris and raise his son James, as well as the child she had recently discovered she was pregnant with. He went to Rome, believing he would find Marty, and he did manage to find Beth, but he was frequently distracted by Fancy Crane, whom it seemed Beth was trying to kill.