Le secret de Son Gohan

It appears that Cell has delivered the final blow to Gohan. But, Gohan is able to recover, and he looks more powerful than ever. He warns Cell that if he is pushed, an unbelievable power will be unleashed. He tells him about the time Raditz came to Earth and he was forced to let loose his amazing strength to save Goku. He also tells Cell about the time he had to do the same thing to save Krillin from Frieza. Instead of being scared by this, Cell is intrigued, and is determined to push Gohan to his limit so he can test himself against this awesome strength. (Source: Wikipedia)