Le sacrifice

With Android 18 no longer a part of Cell, he regresses to his second imperfect form and finds himself absolutely no match for Gohan. Goku pleads with Gohan to end the battle immediately, but Gohan's new found arrogance causes him to simply toy with Cell. In desperation, Cell decides to blow himself up along with the planet, but Goku makes the ultimate sacrifice. He transports Cell to King Kai's planet, and they are destroyed in the blast. Goku has managed to save the Earth from certain doom...at the cost of his own life. As the Z Fighters are mourning the loss of their friend, and Gohan angered that his arrogance caused him to lose his father, Cell suddenly reappears and easily kills Trunks with a single blast. (Source: Wikipedia)