The ever-reliable Ian Hart appears in Part 2 as Harrison's now-adult son and apprentice, and Longitude approaches its dramatic climax with the exhilarating tension of a first-rate thriller. Rallying after sickness to prove the integrity of their marvelous seafaring chronometers, the Harrisons still had to fight for official recognition, and Gould's restoration of the Harrison clockworks provides a fitting coda to this exceptional story about the thrill of discovery and the tenacity of remarkable men.