Desi’s parents fled Vietnam with her 2-year-old brother by boat while her mother was pregnant with Desi. They were put in a refugee camp in Hongkong before they made it to the USA.
One of the first women to graduate from U.S. Army Ranger School, Desi was previously a member of a special ops team consisting of forces from the SAS, Delta Force and the CIA. Desi carries a gun due to regulations, but prefers capturing enemies instead of killing them.
As a friend of Jack Dalton (George Eads) that owes him a favor, Desiree “Desi” Nguyen (Levy Tran) is asked to stand in for him to watch over Team Phoenix while he is on the secondment leading the hunt for wanted murderer Tiberius Kovacs.
Before officially meeting Team Phoenix in Episode 3×15 (K9 + Smugglers + New Recruit), Desi tests the team members and their security protocols. She is appalled to find that only her boss Matty Webber (Meredith Eaton) actually follows said protocols and how easy it is to break into the house of Angus MacGyver (Lucas Till).
Despite stating that she doesn’t want to be friends with co-workers, she starts joining the team for after-work gatherings.
By Episode 3×20 (No Go + High Voltage + Rescue), robot Sparky is programmed to assess human emotion. He comes to the conclusion that MacGyver and Desi share a mutual attraction for each other.
At the end of the Season 3 Finale Episode (Mason + Cable + Choices), Mac and Desi agree to go on a “date”; him telling her about Cairo and her telling him what she owns Jack.
After the events in the Season 3 Finale, the Phoenix Foundation was disbanded and the team members were stripped of their high-level clearances. Being blacklisted to work for another angency, Desi started working as a bouncer.
In Episode 4×01 (Fire + Ashes + Legacy = Phoenix), Russ Taylor (Henry Ian Cusick) approaches MacGyver; convincing him to get the “Team Phoenix” back together. As it turns out, Mac and Desi have dated for several months before the relationship fell apart. The two had adopted a parakeet. After the break-up, Desi got “custody”.
Reboot series (recurring character in Season 3, regular in Season 4)
In Episode 4×05, it’s implied that she’s bisexual.