Why Detective DeMarcus King From Blue Bloods Looks So Familiar

CBS cop drama "Blue Bloods" is a network TV powerhouse, spanning more than 275 episodes across 13 seasons and counting. Driving this success is a simple formula — the series stars an ensemble cast consisting of big names like Donnie Wahlberg, Bridget Moynahan, and Tom Selleck, each of whom plays a member of the Reagan family working for a different branch of New York City law enforcement. While this straightforward setup remains the backbone of its extensive run, the show likewise started evolving right after its very first episode.

Notably, the "Blue Bloods" pilot introduced a character named Detective DeMarcus King as the partner of Detective Danny Reagan (Wahlberg). Together they solve the kidnapping of a missing girl and work on building a case against her captor. But this was ultimately King's sole "Blue Bloods" appearance, meaning that what seemed to be a functional buddy cop tag team was broken up by Season 1, Episode 2.

Playing Detective DeMarcus King is an actor named Flex Alexander, who immediately became one of the first actors to leave "Blue Bloods." His career dates back to the '90s and includes appearances in plenty of popular movies and TV shows, which is probably why he looks so familiar to you.

At the start of his acting career in the '90s, Flex Alexander — born Mark Alexander Knox and credited throughout much of the decade as just "Flex" — established himself as a comedic performer. One of his very first gigs, for example, was on a sketch comedy series titled "Uptown Comedy Club" that also features names like Mary J. Blige and Tracy Morgan.

Following some subsequent comedic work as well as a recurring part on a drama called "Total Security," Alexander debuted as the lead of UPN sitcom "One on One" in 2001. He played a former NBA player named Flex Washington who falls back on a sportscasting career after an injury forces his early retirement. For its first four seasons, much of the show concerned Washington's bachelorhood and his relationship with his daughter Breanna Barnes (Kyla Pratt). The show's fifth and final season, meanwhile, no longer revolved around Washington, although he showed up sporadically nevertheless.

Alexander was nominated multiple times at both the BET Comedy Awards and the NAACP Image Awards for "One on One." In an interview with UrbanBridgez.com, he described Washington as one of his favorite roles, and a character that he felt reflected some of his real-life personality. "A lot of people think my name is Flex Washington," he said with a laugh. "That was definitely one of my favorites."

In 2004, VH1 premiered a TV biopic about the so-called King of Pop titled "Man in the Mirror: The Michael Jackson Story." Playing its subject was none other than Flex Alexander. The film covers decades of Michael Jackson's career, briefly flashing back to his childhood as a member of the Jackson 5 before kicking off its story around the release of the "Thriller" album. This account of Jackson's life continues through a number of controversies that colored the singer's career, concluding with the lead-up to his criminal trial in June 2005.

While the film was met with an overwhelmingly negative reception from critics and viewers, Alexander's performance at least earned him some acclaim, resulting in an NAACP Image Award nomination for Outstanding Actor in a Television Movie, Mini-Series or Dramatic Special. (He also received a nomination for "One on One" that same year.)

In an interview published by Entertainment Weekly around the time of the film's premiere, Alexander shared that he agreed to the role partially due to his personal fandom for Jackson. "I've always been a Michael fan. I wanted to become a Jehovah's Witness," he said. "That's how much of a fan I was." That said, the fact that the film didn't shy away from the darker chapters of Jackson's life foreshadowed even more damning films about the singer, like the 2019 HBO release "Leaving Neverland."

Moviegoers today who weren't necessarily paying attention to the cinematic landscape at the time might have trouble believing the hype leading up to the 2006 Samuel L. Jackson comedy "Snakes on a Plane." Well before "meme" was a word even grandparents might kinda sorta understand, "Snakes on a Plane" was an early example of the phenomenon, inspiring widespread online revelry based on its title and premise alone. Unfortunately, audiences' reception to the final product paled in comparison to that pre-release hype.

"Snakes on a Plane" stars Jackson as an FBI agent who must stop a mob plot to assassinate a witness set to testify in a major murder case. The mob decides to deploy a crate of venomous snakes on this key witness' plane ride to the murder trial, while Jackson's character must protect him as well as the aircraft's other innocent passengers.

One of those passengers is a germophobic rapper named Three Gs, played by Flex Alexander. Amidst the snake-fueled chaos, Three Gs is romantically interested in a wealthy woman named Mercedes (Rachel Blanchard). But more importantly, near the film's conclusion, Three Gs' bodyguard Troy (Kenan Thompson) helps save the day when he uses his past experience with a flight simulator to land the plane in its dead pilot's stead.

After "One on One" established Flex Alexander as a noteworthy talent, he started working semi-regularly in Hollywood through the mid-2000s. In addition to VH1's Michael Jackson biopic and "Snakes on a Plane," he also appeared during this era in films like "Out Cold," "Poor Boy's Game," and the 2007 thriller "The List." Also in 2007, Alexander played a part in a sequel to the remake of "The Hills Have Eyes" that premiered one year prior.

At the start of "The Hills Have Eyes 2," the United States government is attempting to combat the group of mutants that terrorized the protagonists of the first film. Alexander plays Jeff "Sarge" Millstone, the leader of a unit comprised of National Guardsmen trainees sent to deliver supplies to some scientists working on monitoring the mutants. Of course, as soon as Sarge and his team arrive, they find out that something's gone wrong and rededicate themselves to rescuing the missing scientists. Sarge dies relatively early on, leaving it up to the less experienced members of his unit to put a stop to the mutants and their murderous rampage.

After appearing in a total of five movies in 2007, Flex Alexander's feature film work dropped off significantly. The next chapter of his career, however, would see him become a somewhat frequent TV guest star, starting with separate roles in two episodes of "CSI: Miami" that aired in 2007 and 2010. It was after this second episode that he was a part of the "Blue Bloods" pilot. Moving forward, he also worked on single episodes of shows like "Masters of Sex," "Lucifer," "In the Cut," "Station 19," "Grey's Anatomy," and "Kenan."

His longest-running dramatic TV role during this time was as George on "Mixed-ish," the two-season spinoff of ABC's hit sitcom "Black-ish." George is protagonist Alicia Johnson's (Tika Sumpter) neighbor, who visits her alongside his wife Vivica (Kelly Jenrette) in Season 1, Episode 17. As new Black residents of a predominately white neighborhood, they consort with Alicia about feeling like outsiders. He then returns for a couple of Season 2 episodes that aired in 2021. For much of his decades-long film and TV acting career, Alexander was a young up-and-comer, but as George on "Mixed-ish" he plays someone older and wiser than many of the characters that came to define his body of work previously.