John Slattery Joins Jeremy Strong in Paramount+ Limited Series 'The Best of Us'
John Slattery will star opposite Jeremy Strong in 'The Best of Us,' a six-episode Paramount+ limited series about the legal battle that secured nearly $1 billion in compensation for 9/11 first responders who fell ill after the attacks, according to Deadline.
Strong leads the cast as Jason Smith, a class-action lawyer who spent close to a decade fighting for the responders. Slattery plays James Leavitt, the defence lawyer retained by City Hall to push back against Smith's lawsuit. The two sit on opposite sides of a case that Paramount's own press materials describe as a David-versus-Goliath story (Paramount Press Express).
The ensemble is deep. Barry Pepper plays Coach, a former NYPD officer and 9/11 first responder now suffering from leukaemia. Andrea Riseborough is Molly, Coach's wife, watching her husband's health decline and worrying about what comes next for the family. Gaby Hoffmann plays Kathleen McCormick, an FDNY firefighter and activist. Neal Huff is Peter Allen, Jason's colleague at the law firm. Sky Yang rounds out the cast as The Lost Son, a young homeless man.
Tobias Lindholm and Frank Pugliese wrote the series. Lindholm also directs and executive produces; Pugliese executive produces as well. Strong is an executive producer on the project alongside his starring role. The series comes from Paramount Television Studios and Sister, the production company founded by Jane Featherstone and Elisabeth Murdoch.
'The Best of Us' was formerly titled '9/12.' Paramount+ announced the greenlight on October 8, 2025, and production is set to begin in summer 2026 (Paramount Press Express).
For Slattery, the role adds to a busy run across television and film. He is best known for playing Roger Sterling across all seven seasons of 'Mad Men.' More recently, Deadline reported he was cast in USA Network's 'The Rainmaker' series as Leo F. Drummond — a role Jon Voight played in the 1997 film (Deadline). Last year, Deadline also reported his casting in the TV series 'Vladimir' alongside Jessica Henwick and Ellen Robertson (Deadline). Slattery is represented by Gersh.
For Strong, the series follows his acclaimed turn in 'Succession.' 'The Best of Us' gives him another lead role in a project rooted in real events — the kind of long-form, character-driven drama that streaming platforms have built their reputations on.
