Comedian and AP Bio star Patton Oswalt took to social media today in response to the arrest in the Golden State Killer case, a case made famous by his late wife Michelle McNamara in her book I’ll Be Gone in the Dark.

McNamara’s I’ll Be Gone in the Dark, chronicles a serial rapist and murderer who was believed to have killed at least 12 people and raped at least 45 people throughout California during the ’70s and ’80s. In April 2016, she died unexpectedly in her sleep. After her death, Oswalt worked with journalist Billy Jensen and researcher Paul Haynes to finish the book which debuted at No. 1 on the New York Times best-seller list.

When he first heard of the news, he posted a video on Instagram saying, “One of the more surreal days of my life.” He added, “Looks like they got him.”

The celebration of the news continued in a flurry of tweets as he praised his late wife saying, “I hope you got him, Michelle. I hope THEY got him.” In another tweet, he said, “She would be beyond excited about this. I think this is the definition of bittersweet.”

While watching the press conference where they detailed the arrest, Oswalt noted that cops “will never and have never credit a writer or journalist for helping them solve a case.” He said, “But every time they said #GoldenStateKiller they credited the work of #MichelleMcNamara and #IllBeGoneInTheDark.”

He added, “If they’ve really caught the #GoldenStateKiller I hope I get to visit him. Not to gloat or gawk — to ask him the questions that @TrueCrimeDiary wanted answered in her “Letter To An Old Man” at the end of #IllBeGoneInTheDark.”

Deadline recently broke the news that HBO Documentary Films acquired the rights to McNamara’s true-crime book to develop as a docuseries. Oswalt will serve as executive producer.