人類行為
The episode featured a guest performance by Cameron Monaghan as the mind controller Tyler Carson. The actor tweeted after the episode's broadcast, ""Fringe" was cool. What person in the world doesn't wish they had mind-controll powers!" "Of Human Action" also had guest appearances by Andrew Airlie, Peter Graham-Gaudreau, John Tench, Vincent Gale, Jacqueline Ann Steuart, and Doron Bell Jr..