When Liz Ortecho reluctantly returns to her tourist-trap hometown of Roswell, New Mexico, she reconnects with Max Evans, her teenage crush, who is now a Roswell police officer. But Liz soon discovers a shocking truth: Max is an alien who has kept his unearthly abilities hidden his entire life, along with those of his otherworldly sister, Isobel, and their friend Michael. Elsewhere, Master Sergeant Jesse Manes spearheads a long-standing government conspiracy — unbeknownst to his son, Alex Manes, who has recently returned from service overseas with emotional and physical injuries. The politics of fear and hatred that run rampant in Roswell threaten to expose Max and his family and could endanger his deepening romance with Liz…as well as their lives.
The anniversary of Rosa's death reignites tensions as the town takes aim at Liz and her father, Arturo, for what happened on that fateful day 10 years ago. Meanwhile, Max confronts Michael and Isobel, who are concerned that his feelings for Liz will expose their secret. Elsewhere, Master Sergeant Manes' attempt to convince Kyle of the alien conspiracy in Roswell takes an unexpected turn. Finally, Liz and Kyle make a shocking revelation about Rosa's death.
After uncovering some unsettling information about Max, Liz runs a series of tests to see what his powers may be capable of. Michael and Isobel take matters into their own hands after learning that Liz may be getting too close to Max. Liz enlists Maria's help as she goes on a scavenger hunt across Roswell to uncover more about Rosa's final days.
Fearing that his identity will be uncovered, Max is conflicted when a town-wide power outage leaves patients at the hospital in need of help. Meanwhile, Liz turns to Kyle after learning details about the night Rosa died. Elsewhere, Isobel and Michael come up with a plan to deal with Liz, and Master Sargent Manes seeks help from an unlikely source.
Max and Michael begin to worry about Isobel after a series of mysterious blackouts cause her to spiral. Liz turns to Grant Green for help when she learns that he may have witnessed something strange on the night Rosa died. Meanwhile, Kyle and Alex uncover a secret that Kyle's father had been keeping from everyone.
After uncovering a devastating secret about Rosa's death, Liz takes matters into her own hands to protect herself and those around her. However, her plans are sidelined after a day with Mimi, Maria and Alex leads to a new revelation about Rosa. Elsewhere, Max takes aim at Wyatt, while Cameron decides whether she's going to help Sergeant Manes.
Max and Michael travel to Texas to visit a faith healer, who may be able to shed some light on the alien symbol Max has been researching. Meanwhile, Maria and Liz pay a visit to the same faith healer in hopes of finding a cure for Maria's ailing mother. Elsewhere, Alex and Kyle look into what Sergeant Manes may be hiding.
Torn between the heartache of Max's sacrifice and the joy of Rosa's resurrection, Liz suppresses her grief to focus on moving out of Roswell with Rosa. Meanwhile, Michael copes with Max's death in his own self-destructive way, while Isobel focuses her attention on honing her alien powers. Finally, Liz makes an alarming discovery after Rosa begins experiencing mysterious side effects from her resurrection.
Liz is forced to put her latest experiment on hold after Rosa begins to struggle with her new life in Roswell. Reluctant to face the truth about his mother's past, Michael turns his attention to helping Maria, who is dealing with her own family crisis. Elsewhere, Isobel agrees to join her mother for a day of spiritual healing to keep herself distracted. Finally, Rosa turns to Kyle to learn the truth about what really happened the night she died.
Determined to regain control of her life in the aftermath of Noah's death, Isobel makes a risky choice despite its potential consequences. Meanwhile, Alex and Michael work together to unravel the mystery surrounding the night Nora's spaceship crashed in 1947. Elsewhere, Liz makes a surprising confession when Cameron shows up looking for answers about Max.
On the verge of a breakthrough in her quest to save Max, Liz turns to Kyle for one last favor that could potentially land him in hot water. Meanwhile, Michael and Alex's investigation into Nora leads them to a farm, where they meet a historian named Forrest. Elsewhere, Cameron confronts Jesse Manes about her sister's whereabouts, and Isobel uses her powers for good.
Maria's investigation into her mother's disappearance leads her and Alex to the home of a mysterious boot maker named Travis. Meanwhile, on her journey of self-discovery, Isobel's night out leads her into the arms of someone unexpected. Finally, after making some major scientific strides, Liz is dealt a devastating blow.
Liz is forced to revisit a painful part of her past when her mother Helena shows up at the diner unexpectedly. Michael urges Maria to seek help after she experiences a strange vision, and Kyle's attempt to get Steph to open up doesn't go as planned. Finally, Helena's arrival in Roswell sends Rosa spiraling.
Despite promising Liz that he'll take things easy with his new heart, Max sets out to find Cameron after learning that she's gone missing. Michael grows concerned about Maria after a surprising discovery about her family history leaves her vulnerable. Elsewhere, ready to move on, Alex goes on a date with Forrest, and Rosa makes a decision about her future.
After uncovering a surprising connection to their past, Michael and Isobel learn the painful truth about the night Tripp attacked their mothers. Meanwhile, Alex confronts his father about their troubled family history. Elsewhere, Kyle's first date with Steph takes an awkward turn after Liz inadvertently becomes a third wheel.
Driven by the prospects of her scientific research, Liz opens up to Diego about all the good her findings could do. Meanwhile, Max enlists Kyle's help getting to the bottom of the recent abductions, while Michael does his own investigating into Alex's disappearance. Elsewhere, after learning more about her mother Louise, Isobel pays a visit to Rosa, in hopes that Rosa could help her begin to heal.
Having realized that a deadly threat has infiltrated CrashCon, the busiest event of the year, Liz realizes that she can't save everyone she loves -- and with Max facing immediate danger, she and Isobel must make a heart-wrenching choice. Meanwhile, Michael finds himself caught up in the conflict between Jesse and Alex once again, even as Maria's life hangs in the balance elsewhere, and Kyle faces a moral dilemma when the enemy requires medical attention.
With missing friends and mysteries abound, Liz returns to fringe science, but in working alongside her new mentor, she's confronted with an unsettling revelation and a difficult choice, meanwhile, Maria uncovers the truth behind the "messages" she's been receiving. Elsewhere, the bond between brothers is tested when Max keeps an explosive secret from Michael, putting them at odds during a critical moment. Lastly, Isobel tries to pull answers out of Tezca, only to discover that the villain in her story is not as clear-cut as she may seem.