DBZK Episode 33
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Full Power, Goku! Captain Ginyu's Desperate Attack! is the thirty third overall episode in the Dragon Ball Z Kai series. The original Japanese title is "Furu Pawā da Son Gokū! Ononoku Ginyū ni Hisaku Ari!?" (フルパワーだ孫悟空！おののくギニューに秘策あり!?). The episode first aired on November 22nd, 2009. It's original American air date was July 22, 2010.
Goku powers up to his maximum level - which is far greater than Ginyu expected. The captain can do nothing but gawk at his more powerful opponent. After the Grand Elder unlocks Dende's hidden powers and sends him off to meet the Earthlings, Nail begins battling Frieza. While Frieza is clearly the stronger of the two, he is surprised at Nail's ability to regenerate lost limbs. Gohan and Krillin rescue Bulma from a dinosaur attack, and take the Dragon Radar to find where Frieza took the Dragon Balls. As the episode ends, Ginyu makes the strange move of wounding himself, and firing a strange beam at Goku.