Played by Charlotte Ross, Felicity Smoak's mother is coming to back to Star City in a season 6 episode of Arrow. The character's reasons for returning are currently unknown, but her appearance will likely create some waves considering her somewhat rocky relationship with her daughter and past romantic entanglement with Quentin Lance.
The explosion on Lian Yu in the season 5 finale of Arrow created an entirely new mess of problems for Oliver and Team Arrow. In the season 6 premiere, it was revealed that Oliver is now raising William after the death of the boy's mother, Samantha. Oliver is troubled as the character struggles with juggling fatherhood, fighting crime, and serving as the mayor of Star City. The season puts the focus on family as Oliver deals with his relationship with his son, as well as his relationships with each member of Team Arrow.
TVLine reports that Charlotte Ross will reprise her role as Donna Smoak in an unrevealed episode of season 6. No details are known yet of the reasons for Smoak's return, but they could be connected to any number of currently unfolding storylines, such as Felicity's decision to open a new business with Curtis. There's also been a rumor that the 2017 Arrowverse crossover, 'Crisis on Earth-X', which is expected to feature the wedding of Barry and Iris, may actually include a double-wedding. If true, fans may see Oliver and Felicity tie the knot as well. This would easily explain the reason for Donna's return.
Donna first appeared on Arrow in the season 3 episode, 'The Secret Origin of Felicity Smoak', as a character who was in many ways the complete opposite of Felicity with her flirty, outgoing personality and difficulties with technology. Donna raised Felicity alone after her husband, Noah, left them and became an infamous hacker.
The differences between Donna and Felicity strained their relationship, but eventually they grew closer. As Donna developed a stronger presence on Arrow, the character developed a romantic relationship with Quentin Lance that ended off-screen between season 4 and season 5.
Donna hasn't appeared on Arrow since the season 4 finale, 'Schism', where she was nearly killed by Damien Darhk. Afterward, she left town with Lance, who was still reeling from Laurel's death. At the beginning of season 5, it was revealed that the two had broken up. It's possible that her return will lead to Donna rekindling her relationship with Lance, who is in a much different place now that he's working in the mayor's office.
Arrow continues Thursday with 'Next of Kin' @9pm on The CW.