A native of South Los Angeles, Daniel Harrelson was born to Daniel Harrelson, Sr. and Charice Harrelson; he also has a sister, Winnie. When he was a kid, his father left the family after falling in love with another woman and moved to Oakland, California, where he eventually had another daughter, Brianna. Hondo and his dad remained in touch
As a kid, Hondo and two of his best friends Leroy Henderson (portrayed by Michael Beach) and Darryl, ran with a gang, but after Darryl's death, Hondo went to high school and eventually joined the force
A few months before Hondo graduated, he and his father witnessed the 1992 Los Angelos riots. While trying to get home safety, Hondo and Sr saw two black rioters pull a white man from his car and start attacking him. Despite Sr. attempts to keep Hondo in the car, Hondo jumped out the car and ran to intervene. This forced Sr. to also leave his car and help his son. They were able to stop the beating and get the man to the hospital where he was saved. Hondo was left in awe that he and Sr. managed to save someone's life. It's heavily implied that this helped influence his eventual path to the police force
After high school, Hondo enlisted in the United States Marine Corps (USMC). He served four years (1994 to 1998) with the 1st Battalion,9th Marines (1/9th Marines) out of Marine Corps Base Camp Pendleton and deployed to Somalia. Upon leaving the Marines, Hondo joined the Los Angeles Police Department (L.A.P.D.)
Hondo began his Los Angeles Police Department (L.A.P.D.) career as a patrol officer with the 77th Street Area. He served as a patrolman for six years before becoming a member of the Special Weapons and Tactics (S.W.A.T.) team
By 2016, he was serving as a Senior Lead Officer on Sergeant Buck Spivey's (Louis Ferreira) Special Weapons and Tactics (S.W.A.T.) team. He knows everyone in the neighbourhood and treats them all with respect, which is why some of the usually police-distrusting South L.A. residents sometimes trust him with information pertinent to his cases. It is around this time that he had gone on his first date with Elle Trask who was an FBI Agent before her promotion to the District of Columbia. They later broke up the relationship after finding the long distance scenario to be too complicated which Hondo mentioned that he didn't end it too well
In 2017, Hondo was unexpectedly promoted to Team Leader after Buck was fired for accidentally shooting an unarmed black teenager during a shootout. Senior team member Sergeant David Kay (Jay Harrington), who was next in the hierarchy after Buck, was overlooked in a blatant attempt to ease the tensions between the community and the Los Angeles Police Department (L.A.P.D.)
Four months prior to the series, Hondo began a surreptitious romantic relationship with Captain Jessica Cortez (Stephanie Sigman), which, while frowned upon, is not expressly forbidden by Los Angeles Police Department (L.A.P.D.) policy. However, after his promotion to Team Leader, which put him directly under her command, the two struggle to keep their relationship secret. Hondo ultimately breaks up with her after they were caught by Commissioner Michael Plank (Peter Facinelli) in order to protect her career. He later starts a relationship with Nia Wells (Nikiva Dionne a Los Angeles County Deputy District Attorney and recent divorcée, but the relationship is not serious and does not hold long after he told her that he had threatened to come after a man who he accused of drugging his younger half-sister, Briana, and possibly try to take advantage of her one night at a nightclub which was one of the reasons Nia decided to break
