Keamy is introduced in the fifth episode of the fourth season as a crew member aboard the freighter called the Kahana that is offshore the island where most of Lost takes place.
[6] Critics praised the writers for breaking Lost tradition and creating a seemingly heartless character, while Durand's performance and appearance were also reviewed positively.
[8] In fall 2004, Keamy is hired by Widmore to lead a mercenary team to the island via freighter then helicopter and extract Ben for a large sum of money.
[9] Once he captures Ben, Keamy has orders to kill everyone on the island (including the forty-plus survivors of the September 22, 2004 crash of Oceanic Airlines Flight 815: the protagonists of the series) by torching it.
[10] On the night of December 25, helicopter pilot Frank Lapidus (Jeff Fahey) flies Keamy and his mercenary team,[11] which consists of Omar (Anthony Azizi),[7] Lacour, Kocol, Redfern and Mayhew, to the island.
[9] On December 27, the team ambushes several islanders in the jungle, taking Ben's daughter Alex Linus (Tania Raymonde) hostage and killing her boyfriend Karl (Blake Bashoff) and her mother Danielle Rousseau (Mira Furlan).
[12] Upon returning to the freighter, Keamy unsuccessfully attempts to kill Michael Dawson (Harold Perrineau), whom he has discovered is Ben's spy, then obtains the "secondary protocol" from a safe.
In a display of power, Keamy slits the throat of the ship's doctor Ray (Marc Vann) and throws him overboard and later outdraws and shoots Captain Gault (Grant Bowler) during a tense standoff.
[20] Chris Carabott of IGN wrote that "in a show that features characters fraught with uncertainty, Keamy is the polar opposite and his Marine mentality definitely sets him apart.
"[23] According to a featurette in the Lost: The Complete Fourth Season – The Expanded Experience DVD set, Keamy likes "heavy weaponry" and "physical fitness" and dislikes "negotiations" and "doctors".
[26] A former stand-up comic and rapper from Thunder Bay, Ontario, Canada, with the stage name "Kevy D", Durand had seen only around six episodes of Lost by the time he won the part.
"[6] Durand revealed his appreciation for the cast, crew and scripts and the fact that he had the chance to act as someone with a similar physical appearance to himself, as he had previously done roles that had not prompted recognition from viewers on the street.
Despite the antagonist's increasing popularity and fanbase,[6] it became apparent to Durand that fans were hoping for Keamy's death in what promised to be a showdown in the season finale.
Jeff Jensen of Entertainment Weekly commented that Kevin Durand "is emerging as a real find this season; he plays that mercenary part with a scene-stealing mix of menace and damaged vulnerability.
[32] TV Guide's Bruce Fretts agreed with a reader's reaction to Durand's "chilling portrayal" of Keamy and posted it in his weekly column.
[33] Following his demise, Whitney Matheson of USA Today noted that "it seems Keamy, Lost's camouflaged baddie, is turning into a bit of a cult figure."
[34] TV Squad's Bob Sassone thought that the blog was "a great idea" and "funny" and he called Keamy "the Boba Fett of Lost".
[37] The Huffington Post's Jay Glatfelter also called for Keamy's death, stating that "nothing would be better to me than him getting run over by Hurley's Dharma Bus", alluding to a scene in the third-season finale.
"[38] In a review of the season finale, Erin Martell of AOL's TV Squad declared her disappointment in the conclusion of Keamy's arc, stating that "it's always a shame when the hot guys die, [especially when] Kevin Durand did an amazing job with the character … he'll be missed.
"[39] In a later article titled "Lost Season Four Highlights", Martell noted Durand's "strong performance" that was "particularly fun to watch" and wrote that "we [the audience] all know that Widmore's the big bad, but Keamy became the face of evil on the island in his stead.