The cause of death for actress Michelle Trachtenberg has been ruled “undetermined” by the New York City Medical Examiner, according to an agency spokesperson.

While there is no criminality suspected, the city Medical Examiner couldn’t tell what caused the star’s death from a preliminary exam.

Cast members of "Buffy the Vampire Slayer," "Gossip Girl" and more are remembering their co-star Michelle Trachtenberg​ after the news of her death.

Michelle Trachtenberg, the actress who rose to fame as a child star with films like “Harriet the Spy” and went on to have memorable roles on TV shows including “Gossip Girl,” has died, according to an NYPD source.

The longtime actress, who passed away at 39, underwent a liver transplant before her death. Learn more about her health and the challenges she endured.

Police officers, responding to a 911 call, found her unresponsive in a Manhattan apartment on Wednesday morning, the authorities said.

Michelle Trachtenberg was found in her New York City apartment, and the death is not believed to be suspicious, police said.

Actress Michelle Trachtenberg, known for her role in "Gossip Girl," was found dead in a New York City luxury apartment building by the NYPD. She was 39.

From Ed Westwick to David Boreanzaz, how the casts of Gossip Girl, Buffy, and more are paying tribute to Michelle Trachtenberg.