The relationship between Diane and Elwood was troubled for years due to him being an alcoholic and being physically abusive against her. He left the family when Riley was still very young.
When Riley was twelve, Diane began dating Jack Dalton. At the time, Jack was working for the CIA but used the cover of being a bathroom tile salesman. Riley and Jack became very close until he caught Elwood attacking Diane during a visit. Jack gave Elwood a beating of his own, then broke things off with Diane. He left both Diane and Riley behind; claiming he “left for Riley’s sake” as he “didn’t want to screw her up”.
Over the years, Riley developed her hacking skills using the name Artemis37. She took on hacking jobs for a group known as ‘The Collective’ until they requested that she hack the NSA. After saying no, they threatened her mother’s life. Riley carried out the hack as requested but deliberately left a trail to allow herself to get caught and subsequently sentenced to five years in prison. Her logic was that while in prison, she had no access to computers, so they could not make her work for ‘The Collective’ again, meaning they had no reason to threaten her mother anymore.
In the Pilot Episode, Jack recommends Riley to the DXS to find Nikki Carpenter (Tracy Spiridakos) and the bio-weapon she sold. Since the mission is successful, Riley is allowed to join Team Phoenix permanently. Like the other team members, Riley uses the cover of working for a Think Tank.
In Episode 1×11, Riley seemingly disappears. As it turns out, “The Collective” kidnapped Diane, threatening to kill her if Riley doesn’t hack the Chinese government to steal a nuclear weapon. MacGyver, Jack and Riley manage to save both Diane and the US from a nuclear attack. While Diane suspects that Phoenix isn’t just a Think Tank, she still doesn’t know that Riley actually works as an agent on dangerous missions.
Diane spends some time with Team Phoenix at MacGyver’s house in Episode 2×15 when Mac gets a visit from Henry Fletcher. The assassin offers Phoenix to hand in mutual enemy Murdoc (David Dastmalchian) for money. Due to this, Riley’s boss Matty Webber (Meredith Eaton) reveals to Diane that her daughter works for an US intelligence agency.
Reboot series (Seasons 1 and 2)
2×15 Murdoc + Handcuffs
Elwood Davis (married)
Jack Dalton (dating)