David Harbour's alleged mistress is costume designer Natalie Tippett, according to new claims. In the track, Allen sang about Harbour breaking the rules in their "open" marriage. Reacting to the song,

LILY Allen and David Harbour’s blockbuster split has fuelled the pop star’s huge music comeback, with the toxic fallout playing out on her first album in seven years. Cheating

Lily Allen's first album in seven years, 'West End Girl,' is a vulnerable, detailed look into her relationship with David Harbour. But the singer says not all of it is true.

The "Stranger Things" actor and his stepdaughters, whom the singer shares with ex-husband Sam Cooper, visited Universal Epic Universe in Orlando, Fla., on Saturday.

Critics have praised the record as a sharp, witty mix of heartbreak and humor. Across tracks that swing from flamenco to glossy pop, Allen narrates a slow breakup filled with missed calls, open-relationship “agreements,” and the gut-punch discovery of “a shoebox full of handwritten letters from brokenhearted women.”