It's been an emotional day for Patton Oswalt, who learned early this morning that a suspect had been an arrested in the so-called "Golden State Killer" case, made famous by a best-selling book by his late wife, crime writer Michelle McNamara.
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After McNamara, 46, died unexpectedly in her sleep in April 2016, Oswalt worked with a researcher and journalist to finish his late wife's book about the serial rapist and murderer believed to have killed at least 12 people and raped at least 45 people throughout California in the 1970s and 1980s.
The book, "I'll Be Gone in the Dark," debuted at No. 1 on the New York Times best-seller list last month.
As soon as news of the arrest broke, Oswalt, 48, a prolific tweeter, took to social media.
"I hope you got him, Michelle," he tweeted earlier this morning. "I hope THEY got him."
I hope you got him, Michelle.April 25, 2018
When someone commented about how happy Oswalt would be hearing the news, the comedian wrote, "Not as happy as Michelle McNamara."
"She would be beyond excited about this," he later tweeted, adding, "I think this is the definition of 'bittersweet.'"
Bittersweet because McNamara researched her book for many years before she began formally working on it from 2013 until her death.
Following her death, Oswalt worked with investigative journalist Billy Jensen and researcher Paul Haynes to finish the book.
The trio had just finished a book event in McNamara's hometown, Naperville Illinois, where they were also launching production on a documentary about the case, when news of the suspect's arrest broke.
Oswalt called the timing "surreal."
First day of filming on the documentary was yesterday’s book event in Naperville. All of @TrueCrimeDiary’s family was there. Ended with me saying, “He’s running out of time.”— Patton Oswalt (@pattonoswalt) April 25, 2018
And now all of this. Surreal. #IllBeGoneInTheDark #GoldenStateKiller https://t.co/qPXz7a7hRy
As he headed on a plane to New York for press appearances around the book, Oswalt declared in a video on Instagram that he was in "full-tilt freakout."
Oswalt and McNamara were married in 2005 and have one child, daughter Alice, who was born in 2009.
The actor remarried last November to actress Meredith Salenger.
But he said he's committed to finishing the work his wife started, including getting some answers from the Golden State Killer that his late wife always wanted to know.
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. pic.twitter.com/32EHSzBct5— Patton Oswalt (@pattonoswalt) April 25, 2018