On the season five finale of Lost, Jack contributed to the detonation of a nuclear bomb. Was this a mistake or a great plan?

What will happen to Jack and Kate on the final season of Lost? Fans absolutely can't wait to find out, as they're seen here on the season five finale.

On the fifth season finale, Lost viewers were introduced to actor Titus Welliver. He played a pivotal character simply referred to by fans as "The Man in Black."

Jacob makes his first appearance on Lost in the fifth season finale. Then he dies.