Outlaw Queen began in Season 3 where their origins were unveiled. Their relationship officially commenced in (3x18).
When Tinker Bell leads Regina to a tavern, the place where her true love she was destined to be with is, with pixie dust, Regina fears being left and leaves. She only sees that her true love has a lion tattoo on his left hand.
Years later Robin and Regina meet again in the Enchanted Forest after a curse. Regina seemed very rude to him when they first met. During the time they first met in Storybrooke, Robin asks Regina if he could help her in finding the culprit behind the curse, but she says she doesn't remember asking for help. She also tries to walk down the memory lane by asking him if they ever met; he seemed very much familiar to her. Robin tells her he doubts he'd ever forget meeting her but Regina declined it.
The next day, she goes to the funeral of Neal Cassidy to pay her respects. As she goes into the local diner, Tinker Bell approaches her and whispers that the man with the lion tattoo was there. She persuades Regina to go find a chance at true love again, but Regina replies saying she was busy with more important works. Suddenly, Robin approaches her and apologizes to her if he upset her yesterday, to which she says that he did not upset her. Zelena then storms into the diner and threatens to kill Regina and goes away.
A few hours later, she was found by Robin in the forest reading a letter written by Rumpelstiltskin to Cora, praising the magical-skills of her first child. He pick-pocketed the letter from her and read it, stressing the line which said that she was stunning in every way. He asks her what the matter was, and Regina tells him she always thought the letter was pointing to Regina, but now she got to know that it was Zelena the letter was talking about. She further tells him she wouldn't be strong enough to fight her, but Robin encourages her. Without Regina knowing Robin was her true soulmate, they instantly have a connection.
To protect her heart so Zelena wouldn't be able to kill her, she entrusts it to Robin and tells him that he can't steal something that has been given to him after he asks her why he gave such a valuable thing to a thief like him. But the heart threatened his son's life and he gave it back to Zelena through her captive. After a few moments, Regina finally realizes that he is her true love and comes to Robin to tell him so; he felt very sorry for giving her heart to her wicked sister, but Regina doesn't mind it and kisses him passionately. She proved to him that she could love without a heart. Eventually, they fall in love and everything seems fine until Emma Swan and Killian Jones come back from their travel in time with Marian, who turns out to be Robin's dead wife, that separates Regina and Robin because she feels guilty because she killed Marian in the original timeline.
Robin visits Regina after Marian came back, and he tells her that his feelings for her are real. But Regina is afraid, and so Robin goes back home. After an icy spell is cast on Marian and she turns to ice, Regina suggests he give her a true love's kiss. Robin follows Regina and he kisses a sleeping Marian, but the spell did not break. Robin then tells her the kiss could not have worked because he was in love with someone else, i.e Regina. She smiles, but she fears this relationship won't work out too and she resumes her task on trying to break the spell cast on her true love's wife.
As she resumes the task, Robin comes to her and admits he wanted to be with her, but Regina declines this and tells him he needed to forget about her so he could stay with his wife. That night, Robin again comes to her vault and Regina and him have a one night stand. After waking up, she shows him the storybook which recorded the history of every fairy tale character and she wanted to know who the Author was so he could give Regina her happy ending. Robin then goes to the library to find a clue which points to the Author of the storybook and finds a torn page, which had a picture of him and Regina kissing in the tavern where they were supposed to meet. It was labeled 'Page XXII'. He calls Regina and shows her that her fate could have gone many ways and that she was not bound to be a villain. Then, Regina figures along with her friends that Marian was cursed and needed to leave Storybrooke in order to live. Robin and Regina then get separated for real this time.
After some days, Regina and Emma realize that Marian was actually Zelena, and they go to Robin's home and tell him, but he is shocked and tells them that she is pregnant with their child. Because Robin has moved on from Regina they are stuck and Robin does not know how he feels. The two end up falling in love over again and they are happy.
During the season finale, all the fairy tale characters go to a world, which The Author of Henry's Book had created using The Author's Pen, so villains could get their happy endings, in which all the roles of them are inverted; Snow White becomes the Evil Queen, Regina becomes a bandit like Snow White, etc. In this world Regina is confronted by Snow and she is threatened to be killed if she doesn't stop turning everyone against her, but suddenly Robin Hood comes on a horse and carries her away to the tavern.
In the tavern, the two share drinks and Regina comments, saying she expected Robin to look 'dirtier' but Robin scoffs and takes it as a compliment. In this world, Robin is engaged to Zelena and he tells Regina that they would get married the next day. Zelena invites her to the wedding ceremony but Regina says she would like to get a head-start on Snow and she would be busy. But she was lying; when she saw Robin, she had fallen in love with him and so she did not want to bear seeing her happy ending getting ruined again.
The next day, Henry and Emma (who was no more a hero in this world) fight Rumpelstiltskin, who is a heroic knight in the alternate universe, to stop him from stopping Regina crash the wedding of Robin and Zelena. Regina stops at the gate and watches Robin, and he too looks at her. Rumple decides to slash Henry, but Regina comes in the way and she gets injured brutally. Suddenly, they hear the wedding bells ring, indicating that Robin was officially married to Zelena.
The couple and others then rush to see what happened, and Robin comes to Regina's side. He touches her wound and tells her she would not die alone. Then, Henry takes the Author's Pen, and writes that Regina's sacrifice would take all of them to Storybrooke and thus it happens.
After landing in Camelot, King Arthur has organised a ball in honor of the heroes. She and Robin have a dance, and kiss. But then a soldier, Percival, asks for a dance with Regina. He secretly planned to stab her with a sword, but Robin came to her help and he got hurt by the sword. Afraid she might lose Robin too just like she lost her first love Daniel, Regina begs Emma to do something by working her magic out. Pitying Regina, she uses her magic and restores Robin's life and the couple are satisfied.
When Hook unleashed the previous Dark Ones from the Underworld, the heroes realize they must go to Underworld. Regina and Robin willingly go to the Underworld and join the others in rescuing Hook. During this time they also discuss the custody of Zelena and Robin's baby. In the end, the heroes realize it's time to go after rescuing Hook. Hades proposes ambrosia, which could make Hook alive and allow him to return to Storybrooke. Emma and Hook then go underground to search for ambrosia, but they realize the tree has been cut down (which is an act of Hades). Hook asks her to go with the others back to Storybrooke, but Emma refuses. He tells her there would be another way of saving him, and the two share final goodbyes. Then the heroes and Hades return to the town.
After returning, Robin and Regina meet Zelena and persuade her into believing about Hades' wicked plan to get the town under his feet. Zelena thinks they are wrong and she praises Hades by saying about him building the portal so they all could get back to Storybrooke. After much discussion, Regina helps Robin get his daughter back from the Mayor's Office, where she thinks his baby could be, but they realize it has been sealed by a protection spell. Regina suggests they go to the office through an underground tunnel which she built, and Robin agrees.
As they walked, they talked about Zelena finding love with Hades. But, it seemed to Regina that Robin was quite upset with his daughter being in the hands of the God of The Underworld, and gets irked by Regina when she kept defending her sister. When they reach the ending of the tunnel, Regina says she's sorry Robin's daughter was in Hades' hands, and she wanted to make up for it. Robin replies that he too agrees Zelena needed another chance, and everyone has the capability to change. He also softly tells her, "Regina, you are my future." Then the couple kiss and Regina calls Robin 'thief' again.
The two overhear Zelena and Hades talking about the Olympian Crystal. Hades tells Zelena of all that they could have if only they used the Crystal; Zelena only wanted to live with him. Suddenly, they assume someone was watching them. Zelena goes outside to check on it, while Hades followed suit.
Getting into the Mayor's Office since no one was there, Robin takes his little child into his arms and comforts her. Suddenly, Hades appears, and threatens to kill Regina using the Olympian Crystal for trying to turn Zelena against him. He describes it as a very 'powerful' and 'dangerous' weapon, saying it wouldn't kill you; it would end you, i.e, there would be no Underworld or moving on. Robin says it was his plan to get his daughter back, but Hades declines and uses it on her, but Robin steps in front of her which caused him to die. Thus, his soul gets destroyed in the hands of Hades when he saves Regina from getting the same fate. Zelena then comes back to the office and mistakenly the Crystal slips off Hades' hands and Zelena picks it up. He tells her to use it on Regina, but Regina whimpers and tells her softly that true love is sacrifice -- it was what Robin did. Zelena admits this and stabs Hades using the Olympian Crystal. After he dies, Hades' body vanishes fully from the ground and turns to dust while Robin's body was still there. Regina hugs Zelena and they mourn over the loss of their loved ones.
Finally, we see Regina placing an arrow on Robin's grave along with the other residents of Storybrooke paying their respects to him. She also says he never got to name his daughter.
In the final episode of the fifth season, while Emma was trying to find Henry in a search for him, Regina opens a book and finds a letter from Robin, which she opens and reads as follows:
"My dear Regina, I know I shouldn't be writing this but, I had to let you know how proud I am for you. You opened your heart to love, and let it change you. And no matter what separates us, I know you'll always be the heroine woman I fell in love with.
Snow encounters Regina sitting on a bench outside her vault. She sits along with her and they talk about their pasts and how she could become a good person, and briefly about Robin. In the end of the conversation, Regina admits that Hades was wrong; Robin was at peace.
In the final episode of Once Upon a Time, Regina sees Robin again in a dream. In the dream, she tells Robin her son wants her dead. Robin sits beside her and tells her that her life was proof that no one's path is set. Crying, she holds his hand and tells their story was so short and it isn't fair, but he corrects her and tells that the length of their story won't make the story any less epic. In the end of the dream, Robin shoves a red feather into Regina's palms which she does have in her hands after waking up.
On AO3, Outlaw Queen is the fourth most written ship within the Once Upon a Time (TV) tag; Robin's most written, and Regina's second most written.
- MsMojo ranked Outlaw Queen as '#3rd Cutest Couple of Once Upon a Time' in its video, preceded by Captain Swan as #2nd Cutest Couple.