Executive producer/writer/director Brian Armstrong explains the challenges of directing the “stars” of National Geographic’s documentary series “Secrets of the Whales,” streaming now on Disney+  During three years of filming, Armstrong and his crew had to be prepared for almost any possibility while following their unpredictable subjects through all kinds of weather and water conditions. Composer Raphaelle Thibault tells Stacey Wilson Hunt that, as a new mother, her writing was inspired by the compassion and leadership of the female whales.