Alex has deep red hair and bright green eyes. He has "a lean, sinewy body."
Alex's aura color is orange, described variously as "sunny orange," "screaming orange," "bright orange," and "vivid orange."
Alex is the youngest of four sons. His father is a major in the air force, and all of his older brothers have joined the service: Harry and Robert went into the air force, and Jesse went into the marines. Alex is expected to join the service as well, although he does not want to.
Alex becomes romantically involved with Isabel. After one date, Isabel begins seeing Nikolas Branson, who is murdered by Sheriff Valenti. Alex helps Isabel recover from the loss and trauma of seeing Nikolas killed, and they later rekindle their romance.
For the 2019 Roswell, New Mexico television series, Alex Manes is portrayed by Tyler Blackburn. Alex and the other main characters are all aged up ten years, although they still went to high school together, and Alex has become a decorated airman with the air force. Alex is gay in this adaptation and is involved with Michael Guerin, who is bisexual.
↑The Watcher, chapter 12, described by Alex's father: "Senior in high school and he has no idea what he wants to do with his life."
↑Book 1, The Outsider, chapter 4: "Alex spun around to face her. His red hair was mussed, as if he’d been nervously running his fingers through it."
↑Book 1, The Outsider, chapter 11: "Alex didn’t interrupt with questions. He just concentrated on what she had to say, his green eyes locked on her face."
↑Book 2, The Wild One, chapter 1: "Alex had a lean, sinewy body, deep red hair, and these bright green eyes."
↑Book 1, The Outsider, chapter 14: "He gazed around the circle, taking in the deep purple of Isabel’ aura, the warm amber of Liz’s, Alex’s sunny orange, and his own brick red."
↑Book 2, The Wild One, chapter 4: "Once the connection was formed, she could see the auras of each of the others—Max’s clear emerald green, Isabel’s deep purple, Michael’s brick red, Alex’s screaming orange, Liz’s rich amber, and her own a sparkling blue."
↑Book 3, The Seeker, chapter 9: "His emerald green, Michael’s brick red, Maria’s sparkling blue, Liz’s warm amber, Isabel’s rich purple, and Alex’s bright orange combined into that one blinding light."
↑Book 6, The Stowaway, chapter 9: "Alex’s vivid orange aura zoomed into the mix, trailing the scent of almonds."