I'll be honest, when I tuned into the pilot episode of Roswell High, nearly 2 years ago it wasn't to watch this amazing new show that would last about one season before going into the sci-fi blackhole. It was to see if the plot summary in the TV guide was right!

I mean the idea of aliens going to high school in Roswell of all places is a bit of a joke and there was no way that even the best TV writers in the world were going to pull this one off.

I imagined it as being a cheap Breakfast club mixed with the X Files. I was wrong. I was very wrong.

From the opening bars to the theme Here with me sung by the then unknown Dido, Roswell High did the near impossible and pulled me straight into the narrative!

The pilot set out who the aliens/human hybrids (Pod squad) were and why no one knew the truth about them until Max (Jason Behr) saves Liz (Shri Appleby) after she is shot.

What really struck me was how well the actors interplay with each other for a first episode. You actually believed that Max, Michael (Brendan Fehr) and Isobel (Katherine Heigl) grew up together.

As with all programmes of this nature you need a great villain that our heroes can play off of and seeing as this is a High school drama, how about the school 'jock' Kyle and his Sheriff father Jim Valenti.

Add to the fact that Max is in love (and wins the heart of) Liz Parker who is dating Kyle at the start of the series and you have a nice mix.

Now throw in growing pains and the fact that the aliens know little of their origin as well as a mysterious alien named Nasedo (as well as the FBI's X-Files-esque alien hunters) and you have enough problems for our alien heroes to last more than one season!

The reason why Roswell High became so popular so fast is because of the writing. Whereas many shows can start out promising they tend to fade out when the writers start to break the conventions of the world that they have created.

For example in the final series of Quantum Leap believability and continuity was lost when Sam Beckett leaped into the life of one of his ancestors, when one of the primary rules of the show was that Sam could only leap within his own life time.

From the start we know the constraints of the world in which Roswell High exists, but, we also know very little about the aliens history as to who they were on their home planet, so we now have a curve that can be exploited. Whatever we think we know we might not. This is a very handy tool to have and be able to exploit.

The introduction of the mysterious fourth alien Tess and finding out the truth about the mysterious Nasedo at the conclusion of the first series all adds to the mystery that is Roswell High.

By the finale Nasedo, Tess, Kyle and Jim Valenteni have changed from being the villains of the piece to the possible saviors of the Pod Squad.

Possibly the best shock was changing Sheriff Valenti into a father figure for all of the gang (Max, Michael, Isobel, Liz, Maria, Alex, Tess and Kyle) and the uneasy friendships that develops between Max and Kyle after Max saves his life.

At the start of Roswell High we knew little about the characters except that they have special powers to heal and change the molecular structure of things.

By the end we knew that Max and Liz are brother and sister. On their home planet Max was King and married to Tess. Michael was Max's second and married to Isobel. Michael wanted to go home, Maria wanted Michael, Max wanted to be with Liz, Tess wanted to be with Max, Alex wanted Isobel and Isobel wanted to be normal!

In the final episode of Roswell High Sheriff Valenti, Nasedo and Tess help the gang rescue Max from the hands of the FBI's Agent Pierce.

When Michael saves Sheriff Valenti from Agent Pierce (and kills him using his powers), Max brings Kyle back to life after he has been shot friendships are sealed.

The ending of Roswell High was a classic. The Pod squad set off a beacon so that they can see a recording of their real mother. This beacon sets off signals across the globe and heralds a new danger for next season!

With the revelation that Max and Tess are destined to be together and were married, Liz leaves the 1947 crash site so that Max (who still wants Liz) can be with Tess with the strains of Here with Me.

A great tear jerker ending and enough to keep even the sometimes viewer wanting to tune in for another season.

As season 2 of Roswell (sans the High) kicks in the whole gang has grown apart and have became very isolated.

Nasedo is masquerading as Agent Pierce to debunk any reports of aliens to the the FBI. Roswell's female Congress woman is trying to have the sightings investigated while UFO fanatic Brody has taken over the UFO centre.

What makes season 2 unique is the fact that it is like going back to the original storyboard and putting new slants on the series that you would never have imagined. Every newcomer is a potential alien or alien hunter, no one is to be trusted.

This lack of trust goes down to some of the central characters in the show.

There are a lot of new characters and situations which lead to a change in the ones that we trust and these new characters who seem to know more about what is going on than we (the audience) and the central characters do.

To break these changes down we can look at the characters that are introduced:

'Skins'. Aliens who shed their skin and are assigned to seek out and destroy the 'Royal Four'. All but Nicholas are destroyed by Tess when they find the Pod Squad.

Nicholas speaks for Kavar. His sole purpose is to find their religious artifacts the Granolith (which the Pod Squad protect).

Brody was introduced as the new owner of the UFO centre and possible alien. Turns out that he was an alien abtuctee and is in search of extra terrestrials. He is used by Larek when he meets Max at a conference intended to send the Pod Squad home and return Max to the throne (a trick by their enemy Kavar).

'*Skin' Congress woman Whittaker is destroyed by Isobel while protecting Tess. It is Whittaker who reveals to Isobel that as Valandra she betrays her brother and husband. Whittaker is also responsible for the death of Nasedo.

When the Protectors (Nasedo and he other aliens that brought the Pods to earth in 1947) brought the incubation pods to earth in 1947 there was 2 sets of Pods. The first were the rejects brought to earth in case anything happened to the Royal four.

*The Dupes (played by their Roswell alter-egos) were taken to the sewers of New York and are the near mirror image of Isobel, Max, Michael and Tess. The only difference is that they are tougher and have an evil streak. Wrath (Michael), Ava (Tess), Loni (Isobel) kill Zan (Max) and trick Max into going to The Summit in New York so that they can go home and obtain the Granolith (a religious artifact from their home planet. When Max realizes what is going on Wrath and Loni try to kill him but he is saved by Liz with the help of Isobel and Ava (mourning the loss of Zan).

It is from these characters and situations that we see the development of the central characters and the trust and at times lack of it in others and themselves that dominates this series. It makes for some of the most compelling sci-fi drama so far seen on TV.

Max has to come to terms with the knowledge that he was the fallen leader of his planet and that he and Tess are destined to be together. This is aided when a future version of himself visits Liz and tells her that she must ensure that his younger self and Tess get together. In this, one of the earlier episodes of the series the pace is set for the rest of the season.

Isobel is really put through the paces in season 2. Not only does she find out that her former self (Valandra) had betrayed her husband (Michael) and her brother (Max) to their enemy Kavar, but she also has to deal with the loss of her would-be boyfriend. That aside there are some humorous moments as Isobel tries to live her life as a normal girl especially in the Christmas episode.

Michael starts out the series as the loner, the one who will do it by himself, but by the end the roles that Max and Michael have been set have been blurred as Max and Michael grow apart until they reveal how they feel to each other in Vegas. But the greatest revelation is Michael's true feelings towards Maria as he drops the hard man facade. This makes for a great season finale.

Tess is an interesting character as we do not mind that she is splitting up Liz and Max because she is so nice. When she goes to live with Kyle and Sheriff Valenti we see her grow and care. There is some touching moments as Jim tells her that he will stand by her when she becomes pregnant with Max's baby. All this trust will be obliterated and we the audience will feel a sense of anger by the series finale when the plot curve that I mentioned earlier is exploited to the max.

After the events at the crash site at the end of series 1 Liz has become isolated from Max so that Max can live his life with Tess. With the help of future Max, she must ensure that Max and Tess will get together. When she succeeds via making Max think that he has slept with Kyle this splits the two apart. Shri Appleby has some of the most dramatic moments of the series from saving Max from the Dupes to going against Max with accusations about the accident that kills one of the gang.

Maria, the plain talking romantic of the group continue her one way romance with Michael which makes for some interesting moments when 'skin' Courtney makes a play for Michael. We also see the softer side of Maria as her relationship with Michael increases when he becomes her shoulder to cry on and protector when open of the gang dies.

Kyle has found Buddha and despite not trusting Max all that much becomes part of the central narrative. He provides great comedy relief as well as dropping his macho facade. We see the caring side of him as well as his willingness to help and trust. When Isobel wants a little pay back on Max, Kyle helps out with humorous consequences. Ultimately in the end we feel for him when Tess's true motives are revealed.

After nailing Max as being an alleged Alien in the pilot Sheriff Jim Valenti has became the protector who puts his job on the line to ensure the safety of the gang. He is a true father figure and we the audience can feel for him. When Michael is arrested on suspicion of Agent Pierce's murder it is Jim who comforts Michael and promises to help him out. We see the father/daughter bond between Jim and Tess grow and we feel sorry for him when we find out the truth. Bill Saddler is used to playing the villains in movies such as Die Hard 2 but he is better suited to the protector role.

In season one Alex was the always reliable one of the group who would do anything for life friends Maria and Liz as well as being madly in love with Isobel. His death in a car crash towards the end of series 2 makes for some of the most dramatic moments in Roswell. This is sci-fi so there has to be a reason why he died and Max can not save him. His death after the Prom affects everyone and tears the group apart. Liz believes it was an alien (possibly Kavar or one of the Skins) while the official report registers it as a car crash and possible suicide. In the finale we discover the truth which will shake up everything. Alex death brought to an end one of the funniest and at times most touching relationships as both Colin Hanks and (Alex) and Katherine Heigl (Isobel) had real chemistry.

Of all the events that happen in season 2 it is the murder of Alex by Tess that comes as the biggest shock. When Liz suspects that an alien was involved we are to believe that it is an alien that we do not know of.

But when through the course of the narrative we find out that Tess has been using her powers to manipulate Alex into deciphering a book and deliberately getting pregnant (by Max) so that they would have to go home (where Max, Isobel and Michael would be executed due to a deal Nasedo had cut with Kavar so that Tess and their unborn son would live).

At this point we the audience feel a sense of betrayal. We have spent the whole season trusting Tess and in the end she has not only betrayed the characters she has betrayed us. We feel guilty for trusting her and feel for the characters whose lives she has ruined.

The end also questions what Future Max believed to be the solution to their problems. He saw Tess as being vital to their survival, yet he was wrong. It is Future Max that sets off the catalyst that will almost destroy the whole unit and alter the course of their lives forever.

As I have mentioned before this show thrives on breaking what we assume to be true about the show, but, as the series enters it's third series some of the answers might be hidden in the background of series 2.

If you look at Ava, the dupe who helps Liz, Michael, and Isobel save Max. She could easily be the real Queen, removed for a dupe who would be prepared to work for Nasedo. Ava appeared to be everything Tess was not.

As Roswell enters it's third series there are a lot of new areas for them to explore, but it is also the trickiest series for any show of any genre.

You grab the audience for the first series, you keep them interested for the second you either fly or sink in the third. If you can keep the audience interested for the third season you are near enough guaranteed longevity. If not season 4 is a miracle.

Only time will tell if Roswell keeps aiming for the sky. But from where I sit I see no reason for it to fail if it can keep the originality and creativity that has kept it alive for the past 2 season. I look forward to its return.