The bullet that prevented both world's to collapse. Man...honestly, i thought that was it. I thought Olivia was done for. There was no way she could have saved. I was broken. But Walter is the IMPOSSIBLE. He discovered the existence of a parallel Earth. He opened a portal. He co-created everything that was said to be impossible to achieve. "Fringe Science". But he did it. And so did he here. He saved her. One of my best Fringe episode ever. It was intriguing, heartbreaking and breathtaking. The most amazing science fiction show i've ever seen.10/10