Star Trek: Deep Space Nine: In Purgatory's Shadow

"In Purgatory's Shadow" is the 112th episode of the television series Star Trek: Deep Space Nine, the 14th episode of the fifth season. The first half of a two-part episode, it is most notable as the beginning of the Dominion invasion of the Alpha Quadrant. It features the return of several familiar faces, drawing on plot lines previously established in the third, fourth and fifth seasons. It was dedicated "In memory of Derek Garth", a grip on the set of Deep Space Nine who died in an automobile accident.