Born in New York City, New York to parents from the Dominican Republic, Santana's career in show business began with a push from his parents, who wanted to keep him off the tough streets of New York. He began his career at the age of three as an advertising model for a fast food chain. His first screen appearance was as an extra in the Woody Allen film, The Purple Rose of Cairo.
In 1996, he landed the role of Romeo Santana on The Steve Harvey Show. In 2001, he played the role of Jermaine in the movie Flossin. In 2002, he appeared in the VH1TV movie, Play'd: A Hip Hop Story with Toni Braxton. That same year, Santana had a role in the Eddie Murphy comedy Showtime. His last television acting role was on the UPN series, Half & Half; his last film role was a 2003 comedy film, The Blues with Deon Richmond. Merlin has 3 unreleased albums.
On November 9, 2002, Santana was shot in the head and killed as he and his best friend, former child actor Brandon Quintin Adams were in a car leaving another man's home in the Crenshaw District of Los Angeles. Damien Andre Gates fired the shot that entered through the trunk of the vehicle that Santana was in. The bullet penetrated the right-front passenger headrest and entered directly into Santana's head, killing him instantly. Damien was later convicted of the first-degree murder of Santana and the attempted murder of Adams and was sentenced to three consecutive life sentences plus 70 years in prison. Brandon Douglas Bynes received a 23-year sentence after pleading guilty to voluntary manslaughter and assault with a deadly weapon, even though none of the shots fired from his revolver ever entered the vehicle. An officer involved in the case testified that Monique King, reportedly Gates's girlfriend and aged 15 at the time of Santana's death, falsely claimed that Santana had tried to rape her, which prompted Gates and Bynes to attack the car. King received ten years in juvenile custody. Santana was 26 years old at the time of his death. He was buried on November 18, 2002, at Saint Raymond's Cemetery in The Bronx, New York.Merlin died leaving a daughter named Melody Santana.