Sir Keir Starmer has revealed he is watching Netflix's Adolescence with his family and supports a campaign for it to be shown in parliament and schools.
The drama, starring Stephen Graham, depicts the aftermath of the stabbing of a teenage girl - as a 13-year-old boy from her school is arrested for her murder.
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Graham and co-writer Jack Thorne have said they want it to be a show that "causes discussion and makes change", after it was hailed by critics and topped Netflix's charts around the world.
Asked by Labour MP Anneliese Midgley if he backs the creators' calls for it to be aired in parliament and schools, Sir Keir said he does.
He told PMQs: "At home we are watching Adolescence. I've got a 16-year-old boy and a 14-year-old girl, and it's a very good drama to watch.
"This violence carried out by young men, influenced by what they see online, is a real problem.
"It's abhorrent, and we have to tackle it."
MPs want tougher action on online safety
Culture Secretary Lisa Nandy also told Sky News that the issues raised in Adolescence were ones the government should be "acutely aware of".
She said said that although ministers were not considering a ban on smartphones for those under 16, Peter Kyle, the science secretary," is pressing ahead with the Online Harms Act to make sure that we keep people safe online".
Sir Keir's commitment came as Sky News learned around 25 Labour MPs who want tougher action on online safety have formed an informal group and are due to meet next week.
It could pressure the government to take more radical steps, after a private member's bill to raise the age of social media consent from 13 to 16 was watered down because ministers didn't support the measure.
The changes were criticised by Thorne in a recent interview with Sky News, accusing the government of being "frightened of big tech".
Johnathan Brash is among the MPs who backs showing Adolescence in parliament and schools, telling Sky News he found it "so powerful and distressing I immediately went upstairs and gave my son a hug".
The Labour MP for Hartlepool, whose son is eight, said elements of the show could be shown in primary school "with discretion" so children understand the dangers before they are using social media.
He said he will raise the issue with officials at the Department for Education to ensure Sir Keir's "extremely supportive" words are followed through on.
Mr Brash said the government must "protect children from an environment that is increasing hostile and dangerous".
It comes after Sky News revealed teenagers are regularly being served up "horrific" content on social media apps, including violent and sexually explicit material.
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Government 'alert' to 'toxic influencers'
Speaking after PMQs, Sir Keir's spokesman called Adolescence "an incredibly powerful programme that shows the threat of young men carrying out violence from seeing things online".
"Insidious misogyny taking root will be tackled," he added, though he did not say how.
He also said the government is "alert to and taking on" issues raised by Sir Gareth Southgate, after the ex-England manager hit out at "manipulative and toxic influencers" who trick young men into thinking women are against them.
The Online Safety Act, which is being implemented this year, is intended to protect young people from illegal and harmful content with fines for platforms who break the rules coming in this summer.
However, MPs from across the political spectrum want further action to tackle the amount of time children spend on their smartphones.
The Tories want the government to force teachers to ban smartphones from schools, with shadow education secretary Laura Trott revealing she is so concerned she won't allow her children to have one until they are 16.
The government has resisted the measure, saying teachers already have the power to ban phones.
(c) Sky News 2025: Starmer backs campaign to show Adolescence in schools