Despite the threat that Doomsday poses, Clark cannot bring himself to kill Davis–forcing Oliver and his team to take matters into their own hands. Chloe finds herself caught in the conflict between Oliver and Clark, while Lois takes on Tess.

Jack’s decision to put a plan in action in order to set things right on the island is met with some strong resistance by those close to him. Locke assigns Ben a difficult task.

House takes on a case of a patient with two different personalities as a result of having the left and right part of the brain operating independently. Meanwhile, he deals with the aftermath of his night of sex with Cuddy.

Chloe pleads with Clark to end Davis’ life since he can no longer control the beast within him. Tess and her team of meteor freaks help Clark track down Davis.

Jack and Kate find themselves at odds over the direction to take to save their fellow island survivors, Locke further solidifies his stance as leader of “The Others,” and Sawyer and Juliet come under scrutiny from the DHARMA Initiative.

While House tries to cope with his insomnia, he takes on the case of a ballerina whose skin begins to fall off after treatment following the collapse of her lungs during a rehearsal.

Clark discovers the truth behind Davis’ supposed death and angrily confronts Chloe when he realizes that she has been protecting him… but it may already be too late, as Davis ambushes Jimmy and Oliver at the Talon.

On the 100th episode milestone for the series, the time of reckoning has begun when Daniel Faraday comes clean regarding what he knows about the island.

A deaf 14-year old wrestler suffers from hearing problems during a match, but his mother refuses to okay cochlear implants. Meanwhile, House’s insomnia proves a curse… and a blessing.

Nathan tries to prevent Sylar from meeting the President. Sylar has his own agenda regarding his partner. Hiro finds there are consequences that come with the return of his powers.