Moonlight has triumphed over Oscars favourite La La Land to win the top honour at the 2017 Writers Guild of America (WGA) Awards.
Writer and director Barry Jenkins won best original screenplay for the deeply moving coming-of-age drama about a young gay man growing up in Miami. He said the award "means the world to me" as he accepted his award on stage.
It beat off tough competition from Damien Chazelle's awards darling La La Land, Kenneth Lonergan's Manchester By The Sea, the Ruth Negga-starring drama Loving and David Mackenzie's Hell Or High Water.
The win now puts Moonlight back in contention for the Best Picture Award at the Oscars this weekend. While many critics have argued that it deserves to take home the top prize,were that to happen it would prove to be a massive upset with most pundits still expecting the top honour to go to La La Land.
Moonlight, which opened in Ireland to rave reviews last weekend, currently has a 98% rating on Rotten Tomatoes and a 99% score on Metacritic.
In the TV awards, Saturday Night Live, which has been lauded for its sketches based on US President Donald Trump and his advisers, won the gong for best comedy/variety sketch series, while Last Week Tonight With John Oliver won best comedy/variety talk series.
Donald Glover's acclaimed comedy/drama Atlanta won two awards for best new series and best comedy series, while FX's The Americans was named best drama series. American Crime Story: The People v. O.J. Simpson took home the award for best long form adapted series.
Oscar-winning director Oliver Stone was honoured with the Laurel Award for screen-writing achievement at the politically-charged ceremony, where he warned it had become "fashionable" to criticise President Trump.
Accepting the award he told writers that "you can be critical of your government and your society".
He added: "It's fashionable now to take shots at Republicans and Trump and all that, and avoid the Obamas and Clintons.
"In the 13 wars we've started in the last 30 years and the 14 trillion dollars we've spent and the hundreds of thousands of lives perished from this earth, remember it wasn't one leader. It's a system, both Republican and Democrat.
Meanwhile, The West Wing and The Newsroom creator Aaron Sorkin criticised Trump as he accepted the Paddy Chayefsky Laurel Award for television writing achievement.
"We've been told that as coastal elites we're something less than real Americans and that we're out of touch," Sorkin said.
"If you find it mind boggling that living and working in the two largest cities in America makes you less than a real American, you're not the one who's out of touch.
"If you don't find it remotely credible that three to five million people voted illegally in our last election, you're not the one who's out of touch.
"If you don't think that turning away people who are seeking a safe haven from unspeakable brutality is a morally defensible idea, then you're not the one who's less than a real American."
British filmmaker Richard Curtis received the Valentine Davies Award for humanitarian service at the awards ceremony in Los Angeles.
The Comic Relief co-founder, who has written a 10-minute sequel to Love Actually for this year's Red Nose Day, urged people involved within the film and TV industry to use their influence to raise money for charity.