One of my favorite things about the recently concluded television series LOST is its emphasis on character. By the end of the show, we had gotten to know dozens of characters fairly well, while there were others I wished we could have lingered on longer. Indeed, there were five flashback characters I especially hoped to see pop up in the final season. Although they didn't, the show leaves us free to imagine what might have happened to them. I'm glad that they at least were a part of the show for a brief time, making their significance felt through the actions of much more major players. Here are my top five minor flashback characters on LOST.

EssaEssamm Tasir - In the episode The Greater Good, we learn about the sequence of events leading to Sayid being on Flight 815 out of Sydney. These involve Essam, his former college roommate, played by Donnie Keshawarz. A gentle Philosophy major, he became so distraught after the death of his wife in a bombing that he joined with a terrorist cell. When he and Sayid meet up, he is on the verge of a suicide mission. While he professes no fear at the thought of martyring himself, he is deeply troubled by the thought of killing innocent people, and he nearly backs out.

Sayid, who has been recruited by the CIA and its Australian equivalent, the ASIS, to discover the cell's stockpile of explosives, is similarly reluctant to encourage his friend's involvement, even though he knows that the attack will not be brought to fruition. However, the agents coerce Sayid by informing him that they can reunite him with his true love Nadia - and that if he doesn't cooperate, they will see to it that she is deported from America, where she now lives. So Sayid passionately convinces Essam to go through with his plans, and only at the last moment does he inform him of his ulterior motives and urge him to escape. Essam's shocked response is to shoot himself, leading Sayid to remain in Australia longer to bury his body.

LOST had already made a bold move in getting a post-9-11 audience to sympathize deeply with an Iraqi man from the Republican Guard who spent many years torturing people. In this episode, they go so far as to present a reluctant suicide bomber who is one of the most tragic figures on the show. He is the main reason that I could never root for Sayid's Island relationship with fellow castaway Shannon; after his friend died as a result of his desperation to return to Nadia, how could Sayid pursue a different relationship so quickly? Despite his death in this episode, I hoped that the Sideways world of season six would give us some indication that he was alive and engaged in some type of scholarly pursuit. After The Greater Good, however, the show never mentioned Essam again.

Mr. Kwon - This sMr Kwon (27562)eries is completely preoccupied with what one episode title calls "daddy issues". Almost every character on the show has, to some degree, a bad dad. In Jin's case, however, the son is the one who is out of line. The episode ...In Translation casts Jin in a more favorable light than before, and toward the end of the episode, we see him meet with the humble fisherman who raised him. Played by John Shin, this unassuming man welcomes him home with a wide smile and open arms, despite the fact that Jin denied his existence for years out of shame for his simple origins. Reminiscent of the father in the Biblical parable of the Prodigal Son, Mr. Kwon has nothing but joy and gratitude on this occasion, and despite their years apart, he unselfishly encourages Jin to flee Korea with his wife Sun and start a new life in America.

As much as I loved Mr. Kwon after his brief appearance in the first season, my admiration for this character increased in the third season when D.O.C. revealed that he had taken on the task of raising Jin alone even though he most likely was not his biological father. His conversation with Sun reflects the warmth and compassion he showered upon Jin throughout his life and upon his return.

Knowing that he had a granddaughter in Korea, I hoped that we would get some indication that Sun had tried to include him in her life after becoming one of the Oceanic Six. I was especially optimistic during the scene in which Charles Widmore presents Jin with a camera containing pictures of the daughter he has never met; just a snapshot with Mr. Kwon and Ji Yeon together would have been a very powerful image. Alas, there is no such photograph, and Sun never mentions him, so I have every reason to believe that Ji Yeon grows up without realizing that not so far away lives her grandfather, the noblest parent on the show.

Sam AuSam (27560)sten - I love Sam for the same reasons I love Mr. Kwon. An officer in the United States Army, he was the strongest positive influence throughout Kate's upbringing, and for most of her life, she believed him to be her biological father. It's because of Sam that she learned many of the skills that make her such a successful tracker. Like Mr. Kwon, Sam, played by Lindsey Ginter, only appears in two episodes, and he gets more screen time with Sayid than Kate, revealing himself to be an honorable soldier who cares deeply about the daughter from whom he is separated.

Kate's realization that her actual father is not Sam but Wayne, the abusive man her mother loves, is what sets her life as a fugitive into motion. In their scene together, we see that even though Kate has done terrible things and is on the run from authorities, Sam loves her as much as ever, and her affection for him remains despite her disappointment that there is no biological connection. When Kate returned to Los Angeles, I hoped to see Sam waiting for her with open arms, but whether he didn't know of her arrival, couldn't get there in time or didn't think it prudent to go, he didn't show up, and we never saw him again. I would have loved some further acknowledgment of both Sam and Mr. Kwon in the final season, either in the Sideways or just through a mention on the Island, but no such luck.

Tom BrennaTomn - It's funny that two of the characters on this list relate to Kate, who hasn't been one of my favorite characters. Through Tom, however, I eventually came to appreciate one of Kate's defining characteristics. Although she is a reckless renegade who has a knack for getting her friends into life-threatening situations, she is more aware of and troubled by this than she often lets on. Her intensely personal experience of inadvertently causing someone's death casts everything that she does in a new light.

Tom, played by Mackenzie Astin as an adult and Tanner Maguire as a child, was Kate's best friend growing up. A frail boy, he shyly tagged along with Kate's schemes, including her attempt to shoplift a New Kids on the Block lunchbox, which unbeknownst to her was a turning point in her life, as it led to an encounter with the mysterious Jacob, who tapped her on the nose and encouraged her to stop stealing. Kate and Tom remained close throughout their childhood, and the lunchbox became a symbol of their bond when they buried it as a time capsule containing several childhood treasures, including Tom's plastic plane, which Kate goes to great lengths to retrieve later in her life.

While she is on the run, Kate visits Tom, whom she hasn't seen in years, and he agrees to help her see her estranged mother, who has been diagnosed with a terminal illness and is in the hospital. Her mother panics, so Tom helps Kate escape, but upon their return to the car, he urges her to turn herself in. Instead, she pulls off a daring escape, but the car is riddled with bullets from pursuing police, and one of them hits Tom, killing him. From that time forward, Kate is acutely aware of the consequences of her actions, and she is especially concerned about the welfare of the vulnerable. When Jacob at last reveals himself to his remaining Candidates, Kate is the one who confronts him about all the collateral damage for which he is responsible. I had hoped to see Tom alive in the Sideways. What's more, there was such an uncomplicated sweetness about their friendship, I found myself hoping that she would wind up in a romantic relationship with neither Jack nor Sawyer, but instead with Tom. That didn't come to fruition, but he remains a compelling character.

Annie - SAnnieo little is known about this girl portrayed by Madeline Carroll that we don't even have a last name for her. She appeared in just one episode, The Man Behind the Curtain, and she and young Ben Linus, played by Sterling Beaumon, had just three scenes together. Nonetheless, she made a powerful impression on me. Ben, whose mother had died bringing him into the world and whose father resented him as a result, spent the first ten years of his life neglected, and after he came to the Island, this quiet, forlorn boy with the striking spectacles somehow grew up to be the sort of man who kills his own father and orchestrates the kidnapping of children. Manipulative and untrustworthy, Ben Linus has a list of sins a mile long, but in his tender friendship with Annie, we see the potential for something better in this shadowy character.

From the moment she meets Ben, Annie offers him nothing but pure, unconditional friendship. She welcomes him warmly, and we get the sense that this may have been the only significant friendship of his life. Annie's continued importance to him is clear, since we see that more than 30 years later, he still cherishes the doll depicting her, which she made for him and gave him on his birthday. In her brief scenes, Annie comes across as intelligent and virtuous, much like Lily Evans in the Harry Potter series, and I often speculated that her influence on Ben was as pronounced as Lily's on Severus Snape.

In the season three commentary, Damon Lindelof hinted that we weren't done with Annie, which fueled the flames of my speculation. I kept expecting her to show up again at any time, or at least to be mentioned. I thought that perhaps she would reappear in the final season, and her presence would set Ben firmly on the path to righteousness. That she never turned up again was a great disappointment to me, as was Lindelof's snarky dismissal of the question regarding her whereabouts. I wish that there had at least been some indication on the show of what happened to her, since she clearly had either left the Island or died at some point after her last scene with Ben. While I wish we had returned to her, I believe her influence is felt in many of Ben's actions throughout the series, especially in the final season.

Although each of these characters had only a brief physical presence on LOST, I consider them crucial, even though none of them even merited a mention in the final season. So here's to Essam, Mr. Kwon, Sam, Tom and Annie!