In the amnesia puzzler’s golden age (1996-2001), blank-slate protagonists from Christopher Nolan, David Lynch and Shane Black generated their own stories. In every case, these histories ended up rosier and nobler than the depraved violence just beneath the surfaces of “Memento” (2001), “Mulholland Drive” (2001) and “The Long Kiss Goodnight” (1996). So let’s retrace our steps through this forgetful sub-genre, shall we?