Lucifer season 2 episode 15 is titled “Deceptive Little Parasite.” According to the episode synopsis, “Lucifer Morningstar (Tom Ellis) must ignite the flaming sword when it’s found to be the only hope for the family returning home safely. Meanwhile, a therapist and head of admissions at a prestigious private school turns up dead.”
In the Lucifer season 2 episode 15 promo video, Lucifer punches through a wall to retrieve the flaming sword. Then, he tells Charlotte Richards (Tricia Helfer), “It’s the most powerful weapon in the universe.” Later, Linda Martin (Rachael Harris) asks Lucifer about his plan. She says, “The three of you plan to use this flaming sword to open the gates of heaven and go home?” Then, Charlotte tells Lucifer, “Only you can ignite it.” But, Lucifer tries and fails to ignite the sword. Later, Amenadiel (D.B. Woodside) says, “We’ll fix it. There’s plenty of time.” But, Charlotte responds, “Just not for me.” Watch the Lucifer season 2 episode 15 promo video below.