Ep 4. Hysterical Blindness

In Heroes season 4 episode 4, titled "Hysterical Blindness," viewers are introduced to a new character, Emma, who has recently developed an ability to manipulate sound waves. Emma is shown trying to come to terms with her newfound power, as she struggles with the ability to hear everyone's thoughts.

Meanwhile, Claire and her new roommate, Gretchen, continue to investigate the suspicious happenings on campus. They stumble upon a hidden room in the library, which leads them on a path to uncovering a secret organization and their plans for a deadly virus.

Sylar also makes an appearance in this episode, as he seeks out his father in hopes of gaining more insight into his past. The audience is treated to flashbacks of Sylar's childhood, which shed light on how he became the ruthless killer he is today.

As the episode progresses, the various storylines begin to intersect, as Emma's abilities prove useful in Claire and Gretchen's investigation. And just as the heroes seem to be making progress in their fight against the secret organization, they are hit with a devastating betrayal that threatens to upend everything they've worked for.

Overall, "Hysterical Blindness" offers a thrilling episode that keeps viewers on the edge of their seat. The introduction of a new hero and the exploration of Sylar's backstory adds depth to the already complex world of Heroes, and the plot twists ensure that fans will be eager to tune in for more.