Using a stolen Klingon Bird-of-Prey in leiu of the recently destroyed Enterprise, Kirk and his crew use the Slingshot manuver around Earth's sun to travel back in time in hopes of finding a Humpback whale to answer the call of the probe. Arriving in the latter half of the 1900's they are confronted with another problem, the Klingon crystals used in the ship's engines have degraded, leaving them with only limited power. Their problems now compounded, the crew, comprised of only the senior crew, splits into three groups, Kirk and Spock going to find the whales. They find two humpback whales, George and Gracie, in the Cecasian Institute near San Francisco. These two whales, soon to be rereleased into the wild, are perfect for them, if they can act in time to save them.