You are going to Watch Astro Boy (2003) Episode 20 English dubbed online free episodes with HQ / high quality. Stream Anime Astro Boy (2003) Episode 20 Online English dub The Cosmic Giant. The earth is hit by a great meteorite which turns out to be the disassembled pieces of a giant robot. Once the robot is put back together, a secret agent reactivates it and the robot proceeds to wreak havoc. Dr Elefun quickly calls in the military, but they are soon mowed down by the enormously powerful machine. When the robot starts to convert the Earth’s air into poison gas, Dr Elefun reluctantly agrees to allow Astro Boy to fight it. But the gigantic machine proves too much even for Astro Boy’s strength. To defeat the monster, the young robot is forced to resort to stealth.