Season One Regulars: Shiri Appleby, Jason Behr, Katherine Heigl, Majandra Delfino, Brendan Fehr, Colin Hanks, Nick Wechsler, William Sadler
2. The Morning After
4. Leaving Normal
6. 285 South, Part 1
7. River Dog, Part 2
8. Blood Brother
9. Heat Wave
10. The Balance
11. Toy House
12. Into the Woods
13. The Convention
14. Blind Date
15. Independence Day
16. Sexual Healing
18. Tess, Lies & Videotape
19. Four Square
20. Max to the Max
21. The White Room, Part 1
22. Destiny, Part 2
Season Two Regulars: Shiri Appleby, Jason Behr, Katherine Heigl, Majandra Delfino, Brendan Fehr, Colin Hanks, Nick Wechsler, Emilie de Ravin, William Sadler
1. Skin and Bones
Agent Pierce's bones are discovered by a geologist, who takes them to Sheriff Valenti.
Guest Starring: David Conrad, Gretchen Egolf, Jim Ortlieb, Jeremy Davidson, Frank Birney, Jason Peck, Dennis Lipscomb, Sara Downing, Austin Tichenor
2. Ask Not
Max is made leader of the alien quartet and Kyle returns home from football camp with a new attitude.
Guest Starring: Desmond Askew, Gretchen Egolf, Jim Ortlieb, J. G. Hertzler, Sara Downing
Isabels surprise 18th birthday party is interrupted when she recieves flashes of Tess in danger.
Guest Starring: Gretchen Egolf, Sara Downing, Jeremy Davidson, Mary Ellen Trainor
4. Summer of '47
Michael gets a detailed story of the 1947 UFO crash when he interviews a WW2 veteran. The Roswell cast play the tales participants in flashback segments.
Guest Starring: Charles Napier, Eric Saiet
5. The End of the World
Future Max travels back in time to tell Liz that their relationship is doomed. Michael realises Courtney is not what she seems.
Guest Starring: John Doe, Sara Downing, Winnie Holzman
Max, Liz, Isabel and Tess travel to Arizona to attend Congresswoman Whitaker's funeral, and discover that her secret organisation is a group of killer aliens called the Skins.
Guest Starring: Miko Hughes, Gretchen Egolf, Sara Downing, Chris Ellis, Holmes Osborne, Jenny O'Hara
The skins come to Roswell and cause all the humans to disappear so they can hunt down the royal aliens.
Guest Starring: Sara Downing, Miko Hughes, Mary Ellen Trainor, Jenny O'Hara
8. Meet the Dupes, Part 1
The four aliens from the second group of pods come to Roswell.
Guest Starring: Desmond Askew, Garrett M. Brown, Michael Chieffo
9. Max in the City, Part 2
Max and Tess travel to New York City for a meeting of the leaders of their home star system.
Guest Starring: Desmond Askew, Miko Hughes
10. A Roswell Christmas Carol
Max fails to use his powers to save the life of a man who died trying to save his daughter. Haunted, Max must find a way to make amends.
Guest Starring: Desmond Askew, John Littlefield, Garrett M. Brown, Mary Ellen Trainor, Diane Farr
11. To Serve & Protect
Isabel receives warning flashes from an unknown girl buried alive.
Guest Starring: Keith Szarabajka, Jeremy Davidson, Jason Peck, Allison Lange, Robert Katims, Breon Gorman, Devon Gummersall
12. We Are Family
Tess uses her powers to save Kyle from a run-in with Agent Duff ( Erica Gimpel). Sheriff Valenti's assistance in the Laurie Dupree hunt costs him his job.
Guest Starring: Erica Gimpel, Keith Szarabajka, Diane Farr, Allison Lange, Robert Katims, Rachel Winfree, Jason Peck, Devon Gummersall
13. Disturbing Behaviour, Part 1
Guest Starring: Desmond Askew, Allison Lange, Jeremy Davidson, Diane Farr, Heidi Swedberg, Jason Peck
14. How the Other Half Lives, Part 2
Laurie finds her family but the kidnapper finds her soon after.
Guest Starring: Desmond Askew, Jeremy Davidson, Allison Lange, Heidi Swedberg
15. Viva Las Vegas
Feeling sullied by the $50,000 given to him by the Duprees, Michael gathers the gang and heads to Vegas to blow it all.
Guest Starring: Samuel Ball, Linda Pine, Howard George
16. Heart of Mine
When an accident causes Larek's memories to intrude upon Brody's mind, he flips out and takes several people hostage in the UFO.
Guest Starring: Diane Farr, Devon Gummersall
17. Cry Your Name
When Alex is killed in a car crash, the gang try to come to terms with how and why he died.
Guest Starring: John Doe, Mary Ellen Trainor, Garrett M. Brown, Diane Farr, Jo Anderson, Jason Dohring, Jason Peck, Hawthorne James, Ted Rooney
18. It's Too Late and It's Too Bad
A life-shattering event evokes different responses amongst the gang.
Guest Starring: Diane Farr, Jason Peck, Ted Rooney, Devon Gummersall
19. Baby, It's You
Tess discovers that she is pregnant with Max's baby, Maria and Liz search for clues regarding Alex's death.
Guest Starring: Nelly Furtado, Michael Chieffo, Jeff Wadlow, Sean Dwyer
20. Off the Menu
An accident causes Larek's memories to enter Brody's mind with catastrophic consequences. Brody flips out and takes several people hostage.
Guest Starring: Desmond Askew, Diane Farr, Jason Peck, Devon Gummersall
21. The Departure
Max. Isabel, Michael and Tess struggle with farewells on what they believe will be their last night on Earth.
Guest Starring: Diane Farr, Garrett M. Brown, Mary Ellen Trainor, Devon Gummersall
Season Three Regulars: Shiri Appleby, Jason Behr, Katherine Heigl, Majandra Delfino, Brendan Fehr, Nick Wechsler, Adam Rodriguez, William Sadler
Max and Liz are arrested after holding up a convenience store that lies above an underground government storage facility housing the aliens' space ship. Consequently Liz's father forbids her to ever see Max.
Guest Starring: John Doe, Garrett M. Brown, Mary Ellen Trainor, Jo Anderson, Michael Chieffo, Phil Reeves, Yorgo Constantine, Jeanetta Arnette.
2. Michael, the Guys & the Great Snapple Caper
Michael takes a second job as a security guard and winds up getting his entire crew fired. Jim Valenti takes on a new job as a Country and Western singer and Kyle catches Isabel making out with Jesse.
3. Significant Others
With Alex's ghost as her guide, Isabel must confront her fears about love for Jesse. Maria happily discovers a whole new, human side to Michael. Liz and Max struggle to remain together despite her fathers disapproval.
Guest Starring: John Doe, Garrett M. Brown, Mary Ellen Trainor, Jo Anderson, Michael Chieffo, Steven Roy, Martin Starr, Michael Pena, Earl C. Poitier, Ivonne Coll and Colin Hanks
4. Secrets and Lies
A mysterious death leads Max to Los Angeles in search of a shape-shifter, who may hold the key to finding his son.
Guest Starring: Joe Pantoliano, Stephen Tobolowsky, Garrett M. Brown, Mary Ellen Trainor, Bitty Schram, Dayton Callie, Adilah Barnes, Stanley Anderson, John Billingsley
Max discovers that his shape-shifting former guardian is a Hollywood producer, who grudgingly helps him search for his spaceship and Isabel reveals her secret to Max and Michael
Guest Starring: Joe Pantoliano, Mary Ellen Trainor, Richard McGonagle, Missi Pyle, Dylan Kussman, Julie-Anne Liechty, Ron Fassler
6. To Have & to Hold
Just before her wedding, Isabel is tron with doubt when she dreams of her former alien lover, Kivar. Meanwhile, Max agrees to be Jesse's best man while attempting to investigate him at the bachelor party.
Guest Starring: John Doe, Spence Decker, Garrett M. Brown, Mary Ellen Trainor, Ivonne Coll, Greg Zola
Isabel and Jesse's honey moon is interrupted by Kivar, who wants to take Isabel back to Antar. Phillip and Geoff come closer to the truth about the aliens identity and investigate into the disappearance of Tess.
Guest Starring: John Doe, Spence Decker, Garrett M. Brown, Mary Ellen Trainor
8. Behind the Music
Maria's old boyfriend Billy comes to town and rekindles her interest in music and a normal life and Isabel is put under suspicion by her father after she lies to him to save Max.
Guest Starring: Clayne Crawford, Mary Ellen Trainor, Garrett M. Brown
9. Samuel Rising
When an autistic boy speaks to Max, he befriends the boy in the hope that his own child is using him to communicate. Meanwhile Isabel plans the perfect christmas for her and Jesse.
Guest Starring: Gavin Fink, Colleen Flynn, Sean O'Bryan, Navi Rawat
10. A Tale of Two Parties
On New Year's Eve, Max and Maria search for secret party called Enigma in the desert, while Liz stays at the Crashdown to host a party for senior citizens.
Guest Starring: John Doe, Eve Brent
11. I Married an Alien
An old reporter friend of Jesse's suspects Isabel is not what she seems. Isabel pictures herself in a sitcom where Jesse knows the truth about her being an alien.
Guest Starring: John Doe, Kristoffer Polaha, Susan Barnes, Garrett M. Brown
Liz begins to suffer ill effects from being healed by Max and decides she wants a normal life. Maria gets the opportunity to pursue a career in music and heads for New York.
Guest Starring: John Doe, Meredith Scott Lynn, Michael Chieffo, Hal Ozsan, Aki Aleong
Maria goes to New York to record her demo and Liz arrives at the Winnaman Academy School in Vermont. Michael enlists the help of his friends in investigating the murder of his co-worker. Max is forced by a woman to heal her husband, dying of old age.
Guest Starring: Clayne Crawford, Meredith Scott Lynn, Jason Peck, Freda Foh Shen, Ashley Johnson, Martin Starr and Morgan Fairchild
14. Chant Down Babylon
Isabel fights for her life after being shot during a showdown with security guards. Max and Clayton Wheeler struggle for control of the old industrialists amazingly transformed body and Jesse discovers the truth about Isabels alien roots.
Guest Starring: Paul Fitzgerald, Ashley Johnson and Morgan Fairchild
15. Who Died and Made You King?
Following Max's death Michael is put in charge of the aliens and Max and Michael battle it out for leadership. Jesse is kidnapped by Agent Burns who tells him that Max is a murderer and Jesse agrees to spy on the aliens.
Guest Starring: John Doe, Yorgo Constantine, Harry Groener and Garrett M. Brown
A young female pilot enlists the help of Michael to save her father from being killed by the air force, who are trying to cover up his collision with a UFO. Isabels parents discover her secret when they place a video camera in her room and record her using her powers.
Guest Starring: John Doe, Mary Ellen Trainor, Woody Brown, Samantha Shelton, Paul Schulze, Larry Poindexter and Garrett M. Brown
17. Four Aliens and a Baby
Tess escapes from the air force base with her and Max's baby son Zan. The gang are then faced with the decision of whether to turn Tess in to the air force or help her. Isabel and Max are forced to tell their parents about their secret, who say they will help them all they can and Max decides to give Zan up for adoption when Tess tells him that he is human.
Guest Starring: Emilie de Ravin, Mary Ellen Trainor, Woody Brown and Garrett M. Brown
Liz discovers that she can see into the future and has a vision of her and the aliens being shot. Her vision also includes a sci-fi writer who they discover will give a speech at the annual UFO Convention in twelve days. The gang realise they are in great danger and decide to leave after graduation, but the sci-fi author from Liz's vision is a guest speaker on graduation night and the teens are forced to make a quick escape. Jesse departs Isabel and takes a new job in Boston, Valenti becomes Deputy Sheriff and Michael, Isabel, Maria, Kyle and newly-weds Max and Liz leave Roswell... Forever!
Guest Starring: John Doe, Mary Ellen Trainor, Winnie Holzman, Michael Shamus Wiles, Patrick Kilpatrick, Joel McKinnon Miller and Garrett M. Brown