Max a Liz jsou zase spolu. Ani Isabel už není sama. Chodí s právníkem Ramirezem, který pracuje s jejím otcem. Max má vidění, že je jeho syn v nebezpečí a tak se snaží najít jiný způsob jak se dostat zpět domů. Nacházejí kosmickou loď. Jsou však přistiženi a Liz zůstává ve vězení.

Michael má novou práci. Získává nové kamarády. Kvůli krádeži ale všichni přicházejí o místo. Michael má výčitky a tak se snaží vše napravit. Zjišťuje, že není jediný kdo něco ukradl. Kyle viděl Isabel s Ramirezem a Lizin otec přistihl Maxe u Liz. Vyhrožuje mu, že pokud Liz nenechá být, pošle ji na internátní školu.

Isabel se podívá Jessemu Ramirezovi do snu. Tam uvidí, jak ji Jesse žádá o ruku. Obává se tedy, že se to stane ve skutečnosti a že Jesseho ohrozí, když mu o sobě poví pravdu.

Člověk, který řešil vloupání Maxe a Liz byl zabit záhadným způsobem. Liz s Kylem zjišťují, že stejným způsobem byla v Roswellu kdysi zabita herečka při natáčení filmu o mimozemšťanech. Max odjíždí do L.A. aby zjistil podrobnosti. Jak se zdá, zabitý muž byl jen nastrčený herec. Oba nejspíš zabil druhý chameleon z jejich vesmírné lodi.

Right before her wedding, Isabel is torn with doubt when she has erotic dreams of her former alien lover, Kivar. Meanwhile, a reluctant Max agrees to serve as Jesse's best man, while attempting to investigate him at the bachelor party.

After their idyllic wedding, Isabel and Jesse are stalked on their honeymoon by her alien lover Kivar who plots to take her back to their home planet. Learning of this, Max and Michael arrive intent on destroying the alien. Meanwhile, Liz and Maria discover that Philip has begun a secret investigation of Max, including the diappearance of Tess, and he's embroiling Liz's dad into the whole thing.

When an old love visits Maria her passion for music resurfaces, which jeopardizes her relationship with Michael. Meanwhile, while Max's father is still trying to put together all the pieces of his investigation, Isabel joins Max in the quest to stop him.

When Max is fascinated by an intriguing autistic child he wonders if his own lost child is attempting to reach out to him. Meanwhile, Michael plays Santa to Maria and Liz's elves at a charity event. Isabel and Jesse share their first holiday together as husband and wife.

In an attempt to find Roswell's legendary New Year's Rave, Max and Maria join forces. Meanwhile, Liz connects with her father and Isabel helps Kyle find the perfect date for New Year's.

When a journalist friend of Jesse's comes to Roswell, Isabel discovers he's investigating her, Max and Michael, after he witnesses Michael using his powers. Meanwhile, Isabel fantasizes about what her life would be like if Jesse knew her alien secret through the device of a 1960s sitcom a la "Bewitched."

When Liz begins to undergo some strange, alien-like changes to her body, she decides she needs to get as far from Max as she can. In order to separate from him she must leave Roswell to go to boarding school in Vermont. Meanwhile, Maria gets offered a recording contract in New York, but she isn't sure she likes what the record label people are doing to her music to make it "popular."

Michael uncovers a conspiracy at Metachem, when a guard is killed on duty. Michael enlists the aid of Max and Isabel when the investigation takes an alien turn. Meanwhile, Liz has entered boarding school in Vermont and tries to start a new life, and Maria disillusioned by New York goes to visit Liz in Vermont.

Michael, Jesse and Valenti call on a discredited doctor to help the wounded Isabel. Also, Clayton Wheeler undergoes an amazing transformation and soon finds himself drawn to Liz; and Jesse quizzes Michael about Isabel's alien roots.

When the gang attempts to return to their normal lives, they soon find that their lives have gotten a lot more complicated, which includes Jesse attempting to come to terms with his newfound knowledge but matters are complicated when he finds himself under FBI scrutiny, and Max's "death" creates a unique situation within the alien authority structure, resulting in a new King...Michael.

Michael witnesses a fatal crash between a fighter jet and an alien vessel, and embarks on his own investigation leading to the recovery of an artifact. Meanwhile, Isabel spends the day with her mother, who's harboring a secret agenda and is working with her husband to discover Max & Isabel's secret, which leads to a shocking revelation.

Max's quest to find his son ends with the return of Tess and the baby, and the gang find themselves in danger again while trying to protect the child. Meanwhile, Jesse encourages Isabel to reveal her true origins to her parents, and the elder Evanses provide a way to ensure their grandchild's safety.

As their high school graduation approaches, the gang must come to terms with their expectations for the future, while joining together to thwart the FBI when they discover that several members of the group are under surveillance. Meanwhile, Liz begins exhibiting even more alien-like powers, that cause her to see visions of their future - including their deaths.