The starship encounters a rift in spacetime while on a routine mission. As they monitor the anomaly, the heavily damaged USS "Enterprise"-C, a ship believed to have been destroyed more than two decades earlier, emerges. Instantly, the "Enterprise"-D undergoes a sudden and radical change from its current timeline: it is now a warship, and the United Federation of Planets is at war with the Klingons. Neither Worf nor Counselor Troi are seen or referred to, and Tasha Yar – who was killed years before – is now running the tactical station. None of the crew notice the change, but Guinan senses that reality has shifted, and has a meeting with Captain Picard to discuss her concerns. She senses that there are supposed to be children on the ship, which of course is completely impractical on a warship. She suggests that the "Enterprise"-C does not belong in their time and must return to the past. Picard, who knows that this would be a suicide mission, refuses to give such an order based on Guinan's intuition alone.