Alex Charles Whitman is the male best friend on "Roswell" to Liz and Maria. He is the computer geek and not terribly cool, although he has a band (Colin plays bass guitar) and his own personal style. He is a very nervous, warm, and funny guy and a loyal friend. He was kept 'out of the loop' of the alien secret for a long time, driving a wedge between him and Liz and Maria, making him very angry. His friendship with them was severely tested when they chose not to reveal Max, Michael and Isabel’s secret, while asking him to do things that bordered on the illegal. Alex is extremely intelligent, but also sensitive, and is completely loyal to Liz and Maria. Alex showed a lot of courage in agreeing to donate blood for Max in "Blood Brothers" without really knowing the reason why, and he used his computer skills to expose the evil Ms. Topolsky. Alex stood up to Liz at school, and faced down Sheriff Valenti when Valenti tried to coerce him and Liz into revealing what they knew about Max Evans by imprisoning them. It was one of Alex's finest hours.
Alex has a crush on Isabel, as was revealed when she 'dreamwalks' him while he is sleeping. This intrigues Isabel and she begins to like Alex. When the aliens' secret is finally revealed to Alex - and once he believes it - he greets the news with a great deal of curiosity and scientific interest and exuberant enthusiasm. He becomes closer to Isabel, even though, like Max, she does not think it is a good idea to have a relationship with anyone human. He drags his bookish father along on a camping trip, and spends some quality time with Isabel under the stars. Alex remains the staunch friend, helping and supporting his friends any way he can, using his knowledge to provide technical expertise.
Alex is also a very good sport. In the beginning of the second season, he entertains Isabel at her surprise birthday party with an energetic and very embarrassing striptease number. Their relationship has never really gotten off the ground, although they were quite close and romantic for awhile. Alex is happy to be there for Isabel and let her lean on him for strength. Isabel starts dating geologist Grant Sorensen and is just not that interested in the devoted Alex 'that way.' Alex has not had a big role second season (Colin has been off working on various films) but he went as an exchange student to Sweden for a month and came back much more confident and mature - and still the nicest guy and best friend.