Two decades ago, NOVA began following the careers of seven doctors, starting with their first day at Harvard Medical School. Now this two-part documentary takes a final, intimate look at them in their 40s. The diverse group includes an iconoclastic emergency physician who’s on his fourth marriage, an idealist dedicated to working with the poor, and an anesthesiologist cultivating a passion for golf. In key moments culled from 700 hours of video footage, their personalities are thrown into relief by times of triumph and heartbreak, generating real-life drama as compelling as anything portrayed on ER or Grey’s Anatomy. Tuesdays, April 7 and 14, at 8 p.m., PBS; check local listings