Originally Posted by Jetée

[I]

Sources confirm to me exclusively that John Lithgow is joining the season 4 cast as Walter Simmons, an unassuming suburbanite who has been living a dual life as one of America’s most prolific and deadliest serial killers. When the mad man (who is dubbed the "Trinity Killer" because he always kills in threes) relocates to Miami, Dexter becomes obsessed (or inspired?) by his efficient killing methods and ability to evade capture for almost three decades.