PBS | 9:00 pm

Butterflies aren't just beautiful and fragile. Their hidden scientific secrets reveal them to be far more inventive and resilient than anyone ever imagined. A new episode called "Butterfly Blueprints" explores their extraordinary life cycle and regular migrations to terrains ranging from tropical rainforests to windswept prairies. Extraordinary footage also takes viewers inside a chrysalis as it is being spun. The study of butterflies also is inspiring groundbreaking technology.