The second season was designed to contain three volumes called Generations, Exodus, and Villains, but Exodus was scrapped due to viewer criticism and the 2007–08 Writers Guild of America strike.
Musim kedua dirancang untuk terdiri dari tiga volume berjudul Generations, Exodus, dan Villains, namun Exodus ditangguhkan karena kritikan dari penonton dan mogok kerja Writers Guild of America 2007–08.