Late Friday night news broke that Michelle McNamara, crime writer and wife of comedian Patton Oswalt, had died suddenly at the age of 46.

Comedy fans may know Oswalt from his prolific stand-up career or his supporting roles in TV shows such as "The United States of Tara" and "King of Queens."

Over the years, Oswalt has become the voice of reason for those in the comedy world. He's become just as known for his open social media persona as he is for his comedy.

Industry sources told NBC News that McNamara's death came as a complete shock to her family and friends. No cause of death was immediately reported, although Oswalt's publicist told the news organization McNamara died in her sleep.

She was known to fiction fans for her impressive career as a crime fiction writer. She was also frequently mentioned in Oswalt's comedy act.

For much of the last decade, McNamara has published from a true crime story blog that detailed her efforts to delve into some of the greatest mysteries of our time.

"I wanted to get more involved in the cases that were fueling my own curiosity," she said in an interview in 2007.

On Friday night, Oswalt retweeted a link to an article about his wife’s death.

McNamara was 46. She is survived by her husband and their 7-year-old daughter.

Fans quickly reacted to the news, including actress Anna Kendrick and comedian John Mulaney.