“Let’s Do It!” is a story about how a national cleanup campaign in a small European country grew into an ambitious global environmental movement. The idea spread far and wide, bringing about new wave of civic activism in many countries. However, even good initiatives can hit rough spots. The important thing is not to lose hope. This documentary captures the passion to change the world over the course of 10 years, culminating in World Clean-Up Day in 2018. The movie also showcases how grass-root initiatives can grow and subside and how some ambitions can be defeated only to give rise to even more ambitious ones.