They first met when Thor, under the human identity of Dr. Donald Blake, hired Jane Foster to assist him in his private medical practice. Thor fell deeply in love with Jane, who was unaware of his dual-identity. Jane was infatuated with Blake, whom she had not yet met in his godly identity, but took a protective attitude toward him, worrying about his health and frailty. Thor feared that Jane did not love him, but merely pitied him.
Thor's foster brother Loki, knowing his feelings toward Foster, endangered her life in order to attack him several times. Afterward, Thor decided to reveal his true identity to Foster, but his father, Odin, king of Asgard, appeared to him and forbade him to reveal this secret to any mortal. Even though Odin tried for a long time to quash the romance between the two, he ordered her life to be saved when she lay dying after an explosion caused by a battle between Thor, Mister Hyde, and Cobra.
Jane truly loved Blake, and one day she told him angrily that she would not wait forever for him to declare his love to her. He intended to marry her, but Odin then forbade him to marry her on the grounds that she was a mortal, not a goddess. Thor later asked Odin to reconsider the issue, and Odin relented, saying that Thor could marry her if she proved herself worthy.
The superhuman criminal Mister Hyde, seeking vengeance against Blake, captured both him and Jane, and trapped him in a room with a bomb. Blake escaped and, as Thor, battled Hyde; but Jane, fearing that only Hyde could save Blake's life by deactivating the bomb, helped Hyde to escape. Outraged by this seeming betrayal against his son, Odin rejected Thor's petition to marry Jane. Foster was menaced repeatedly by enemies of Thor who either knew he was Blake, or knew there was some connection between Thor and Blake. Such assailants included Hyde and his partner, the Cobra; his bitter foster-brother Loki; and the Enchantress and her partner, the original Executioner; as well as the journalist Harris Hobbs. As Thor rescued her from these many perils over time, Jane fell deeply in love with him.
Finally, Thor defied Odin and revealed his true identity to Jane. She left America and took a position with a man who proved to be the High Evolutionary. Thor followed her to the High Evolutionary's citadel at Wundagore Mountain, where they were reunited. Again petitioning Odin to let him marry Jane, Thor brought her to Asgard itself, a place forbidden to mortals.
Odin agreed to let them marry if Jane proved herself capable of functioning as an Asgardian goddess. Odin then physically transformed Jane into an Asgardian, granting her superhuman powers. As Odin must have expected, Jane was confused and bewildered by her new abilities and by Asgard itself. Declaring that Jane had failed his test, Odin turned her back into a mortal woman, sent her back to Earth, and removed her memories of her experiences with Thor. Odin sent Jane to work for physician Dr. Keith Kincaid, and the two soon fell in love with each other.
As for Thor, Odin saw to it that he was reunited the Asgardian goddess Sif, whom he had loved in the past, and their romance was quickly rekindled. Years later, Jane fell ill and, lying close to death, called out to Thor in her delirium. Sif stole the enchanted Runestaff of Kamo Tharnn, the Elder of the Universe known as the Possessor, and used it to infuse her own life-force into Jane, thereby saving her life. Sif vanished, and Jane recovered, also regaining her lost memories of Thor. The two resumed their relationship, but she was soon captured by trolls under the leadership of Thor's enemy Ulik. To Thor's surprise, Jane succeeded in capturing the troll king Geirrodur with his own spear; Thor himself defeated Ulik.
Thereafter, Jane insisted on accompanying Thor on various exploits, traveling with him to the dimension of the god of Heliopolis, to the alternate future Earth ruled by the Tomorrow Man, and to the war-torn nation of Costa Verde (Thor attributed Jane's new taste for adventure and fighting spirit to the presence of Sif's spirit within her, although it is possible that Jane's personality had simply evolved this way on its own). After some time, Jane finally insisted on accompanying Thor to Asgard. There, the Asgardian Grand Vizier presented her with Sif's sword, and when she struck it against a wall, she was seemingly transformed into Sif. The Vizier theorized that Jane and Sif had become one being, and that Sif would be dominant in Asgard, and Jane on Earth. Yet when Sif returned to Earth many months later, she did not transform into Jane, to Thor's puzzlement.
Kincaid eventually launched an investigation into the whereabouts of Jane whom he had no seen since her hospitalization. Thor revealed his true identity to Kincaid and explained what had happened to her. Thor and Sif took Kincaid with them on a journey to the world of Kamo Tharnn, where it was revealed that when Sif infused Jane with her life-force, Sif's own spirit and body had actually passed through the Runestaff and into another dimension. When Sif had reappeared in Asgard, Jane had taken her place in the other dimension. When Kamo Tharnn somehow absorbed the denizens of the latter world into his own body, Sif and Thor used the Runestaff to release the beings trapped within the Possessor, including Jane. Thor and Sif brought Foster and Kincaid back to Earth, and Jane and Kincaid were married almost immediately afterward. They eventually had a son named Jimmy together.
Later, upon hearing of the return of Donald Blake and Thor, Jane divorced her husband and subsequently lost custody of her son. Thor visited her at the hospital in New York City where she worked in search of Sif, whose spirit he mistakenly thought had been reborn in Jane since their spirits had been merged once before. The two went on a date after an initially turbulent reunion. Jane discovered that Sif's spirit had actually been reborn in the body of a dying elderly cancer patient who was under her care. She alerted Thor, who managed to restore Sif just before the patient died. Jane then traveled to Broxton, Oklahoma, the site of the resurrected City of Asgard, and opened a medical practice with Thor.
While Thor was away fighting Gorr the God Butcher, Jane was diagnosed with breast cancer. She later accepted Thor's invitation to represent Earth in the Congress of Worlds on Asgard while she underwent therapy, but refused magical treatments. During a battle against Nick Fury, Thor lost the ability to wield his hammer Mjolnir. The hammer remained unattended on the Moon, where it telepathically sought Jane out. Jane eventually gave in to the hammer's call, and requested Heimdall to take her to the hammer's location. Once there, Jane lifted Mjolnir, gaining Thor's powers and transforming and improving her physique. Since she had watched Thor use his hammer, Jane slowly learned how to use Mjolnir by example.
The original Thor soon caught up with Jane, unaware of her true identity, and demanded to have his hammer back. He ultimately accepted that the hammer had a new owner and gave Jane his blessing. He also gave Jane his name, and subsequently went by Odinson only.
She continued to transform into Thor for some time. This was, however, slowly killing her. All progress from her chemotherapy was lost whenever she transformed; as the magical transformation purged all toxins from her body, it did so to the chemotherapy drugs, but left the cancer behind, as it was part of her body. The cancer metastatized and progressed to stage four, and she eventually came to the point where if she transformed one more time, she would die. She was forced to transform for the last time to save Asgardia from being destroyed by Mangog. He eventually defeated him by binding him in chains originally meant for Fenris Wolf and hurling her hammer into the Sun, taking Mangog with it. She shared one final kiss with Odinson before reverting back to her human form and succumbing to her cancer. Odinson fled Asgardia before it exploded and landed on the Moon where his fellow Asgardians had evacuated to. Refusing to accept Foster's death, Odinson channeled the God Tempest that had been contained within the now-destroyed Mjolnir and tried to use its power to bring Jane back to life. At the same time, Jane's soul stood hesitant at the gates of Valhalla. Having come to accept Jane as one of their own due to her sacrifice, Odin joined his son's efforts, and together they revived her. Without Mjolnir's power to transform her, Jane focused her undivided attention to chemotherapy. She additionally convinced Odinson to reclaim his name and continue fighting the War of the Realms on her behalf.
Jane, an astrophysicist, was in the desert just outside Puente Antiguo, New Mexico researching a mysterious weather event with her colleague Erik Selvig and intern Darcy Lewis. The weather event unexpectedly resulted in a powerful vortex before them. As they struggled with the zero-visibility conditions, their van collided with a man who had stumbled out of the dust into their path. The man, who only announced himself as Thor, was injured again when Darcy tazered him, prompting them to take him to hospital. Thor later escaped the hospital, where Jane once again accidentally hit him with her van. They took him to a diner, where Jane pressed him for information about the vortex. Thor intended to retrieve his hammer. Erik discouraged Jane from helping him. They parted ways, with Thor kissing Jane's knuckles before he left.
Later, after S.H.I.E.L.D. had confiscated her equipment, Jane happened upon Thor again and agreed to drive him to the site of his hammer. After Thor's unsuccessful attempt to retrieve his hammer and his subsequent arrest, Jane enlisted Erik to help get him released. Though Phil Coulson did not believe the fake story Erik told him, he let Thor go anyway. On his way out, Thor took Jane's notebook.
Erik and Thor went to a bar after his release, where Erik warned Thor to stay away from Jane. After several rounds of drinks, Thor showed up to Jane's trailer with a drunk Erik in tow. Jane and Thor went to the roof to talk. To her delight, Thor returned her notebook to her. He explained the Nine Realms to her, and they grew closer to each other.
The next morning, Thor helped cook breakfast for the four of them. The quiet morning was interrupted by the arrival of Sif and the Warriors Three, and the subsequent arrival of the Destroyer. Sif and the Warriors Three fought the Destroyer while Thor, Jane, Erik, and Darcy evacuated civilians. Thor, realizing that the Destroyer had come for him, gave himself up. The Destroyer fatally struck him. Jane ran to him as he lay dying. Due to his sacrifice, he was deemed worthy once more, and Mjolnir returned to his hand, restoring him to life. After defeating the Destroyer, Thor returned to his friends, where Jane complimented his normal Asgardian look. He flew with Jane to the site of the Bifrost. The two kissed passionately before Thor returned to Asgard, with him promising to return. However, he was forced to destroy the Bifrost in order to defeat Loki, preventing him from returning.
For years after Thor left, Jane struggled to move on. She even tried to build an artificial portal to reunite with him on Asgard, though her attempt was unsuccessful.
Coulson assured Thor that they had transported Jane to a remote island, and that she would be safe in the ensuing alien invasion.
Thor: The Dark World
Due to the Convergence, Jane was pulled through a portal into an alien world, where she was infected with the Aether. Thor became worried for Jane's safety after Heimdall informed him that he could not see her, and traveled to Earth to investigate. Jane, who had since woken up back on Earth, slapped him upon seeing him to make sure he was real. She then slapped him a second time and demanded to know where he'd been for the past few years. They nearly kissed, but were interrupted by Darcy.
When police tried to arrest Jane for trespassing on private property, the Aether lashed out to protect its host, letting out a blast of energy that knocked the police away. Realizing that her infection was beyond human treatment, Thor brought her to Asgard for treatment. He was the only one who could touch her without the Aether reacting violently.
In Asgard, Odin informed her that she was hosting the Aether and revealed its history with the Dark Elves. Afterwards, she and Thor walked around the palace, and Thor explained the Convergence to her and kissed her. Dark Elves invaded Asgard soon after, and Thor left to defend his people.
After a devastating battle that killed Thor's mother Frigga, Thor, Jane, and Loki traveled to Svartalfheim, the home world of the Dark Elves, against Odin's orders. Malekith, the leader of the Dark Elves, removed the Aether from Jane's body and absorbed it into his own. Thor attempted to destroy both Malekith and the Aether, but was unable to. Loki was seemingly killed in the ensuing fight.
While exploring a cave, Thor and Jane came upon a Convergence-induced portal that took them back to Earth. In the subsequent battle with Malekith, as Thor fought him, Jane and Erik assisted from the sidelines, using Erik's equipment to harness the Convergence to make portals and teleport enemies away. After Thor defeated Malekith, as he lay unconscious, Jane ran to him to try to pull him away, as Malekith's ship had deactivated and was about to fall on top of him. Unable to move him, Jane was prepared to die with him, but a portal appeared and teleported the ship to Svartalfheim, leaving Thor and Jane unharmed.
After returning to Asgard to speak with Odin one last time (actually Loki in disguise), Thor came back to Earth to live indefinitely. He and Jane shared a passionate kiss upon his return.
Following the Ultron Offensive, Thor left Earth again to learn more about the Infinity Stones. Jane, unable to cope with him leaving her again, broke up with him. A woman taking a picture with him offered her condolences for the breakup.
Many comic fans were disappointed with the way the relationship was handled in the MCU. Although there were those that enjoyed it. Many often citing the way that Thor treats Jane as respectful and sweet.
- Jane – “So, is this how you normally look?”
- Thor – “More or less.”
- Jane – “It's a good look.”
- — Thor receiving his powers back, Thor (2011)
- “I must go back to Asgard, but I give you my word. I will return, for you.”
- —Thor, Thor (2011)
- Jane – “Where were you?”
- Thor – “Where were you? Heimdall could not see you.”
- Jane – “I was right here where you left me. I was waiting, and then I was crying, and then I went out looking for you. You said you were coming back!”
- — Thor: The Dark World
- Thor – “I'd rather be a good man than a great king.”
- Loki disguised as Odin – “Is this my son I hear? Or the woman he loves?”
- ―Thor: The Dark World