Show Business: He has a hot TV series, a new book - and a booming comedy empire

The bedroom is pitch dark. Two young brothers who share a crowded bed are busily not going to sleep. As one of them, Bill Cosby, describes it years later in a classic monologue, the night is an extended comedy-drama of horseplay, taunting and hand-to-hand combat: "I'm tellin' Dad, I'm tellin' Dad . . ." "I never hit you, I never hit you . . ." Each outburst is followed by a visit from their father, who thunders like Zeus, "If I hear any more laughing . . . I'm going to KILL YOU!"

Flash forward. Cosby is the father now, presiding...