Need to Know (House)

"Need to Know" is the eleventh episode of the second season of House, which premiered on Fox on February 7, 2006.

The episode begins by showing Margo Dalton, a "superwife". After a twinge in her arm, she begins an uncontrollable series of muscle spasms. House suspects Margo may be pregnant and gives her a paralytic so they can run some tests. The tests reveal that Margo is not pregnant. Margo displays sudden irritability, which confirms Foreman's suspicion of Huntington's disease.

Wilson confronts Stacy over her kiss with House and warns she cannot toy with him. She admits she does not know what she's doing.

Margo has a psychotic breakdown, leading House to suspect that Margo is using cocaine. Cameron and Foreman find Margo's daughter's Ritalin in the car while searching her house for drugs. House suspects they're the cause of her symptoms. When Foreman chooses not to release her until it's confirmed, House goes to visit the family. He interrogates Stella and determines she's not taking her Ritalin. Margo reveals she never gave Stella the Ritalin and instead used it herself.

House then visits Stacy, who reveals she's leaving now that Mark is getting better. House argues that she loves him more than Mark and he does not want her to leave. Margo is discharged, but while leaving she has a stroke and collapses. Cameron calls House with the news. It is revealed that he is in bed with Stacy at his side.

The team begins to work on diagnosing Margo's new symptoms. House suspects the fertility treatments caused endometrial cancer. On the roof, Stacy meets with House. He wants to know if she is going to tell Mark about their affair, but she stalls.

Margo's initial tests for cancer come back negative, but House persists and orders a biopsy to find the suspected tumor. During Margo's biopsy, she begins to bleed from her uterus. They determine the blood is coming from her liver, leading them to suspect a tumor there instead.

While Stacy goes to Cuddy for advice on how to proceed concerning her situation with House, Mark comes to House asking for advice, concerned that he's shutting Stacy out. House goes up a flight of stairs to avoid him, but Mark tries to follow him and collapses. House refuses to help him.

House is not convinced that the symptoms indicate a liver tumor and takes another look at her history. House suspects that Margo was secretly using birth control pills to negate the fertility treatments, believing that she did not want a child even though her husband did. The combination of Ritalin, birth control, and fertility treatments caused the tumor, which House believes should be benign. But Margo still claims she's not taking the pills and insists on undergoing surgery despite the risks. The surgery reveals the benign tumor that House suspected. Margo asks Foreman to lie to her husband and claim she cannot take fertility treatments any more. Foreman refuses.