Which 2018 action spy film, the sixth in its series, sees Ethan Hunt and his IMF team, joined by CIA assassin August Walker, race against time to prevent a global catastrophe involving stolen plutonium cores?

"Mission: Impossible - Fallout (Review)," released in 2018, is indeed the sixth installment in the thrilling Mission: Impossible film series, starring Tom Cruise as the iconic IMF agent Ethan Hunt. This film plunges Hunt and his Impossible Missions Force (IMF) team into a desperate race against time after a mission to recover stolen plutonium cores goes awry. Hunt's decision to save his teammate Luther Stickell over securing the plutonium allows a terrorist group known as the Apostles to escape with the dangerous material, setting the stage for a global catastrophe.

The stakes are further raised when CIA assassin August Walker, portrayed by Henry Cavill, is assigned to work alongside Hunt, creating an immediate tension due to their differing methods. Walker, however, has ulterior motives, eventually revealed to be the enigmatic extremist John Lark, who plans to detonate nuclear bombs to dismantle the existing world order. The film is renowned for its intricate plot twists, breathtaking practical stunts performed by Cruise himself—including a high-altitude low-opening (HALO) jump and a helicopter chase—and its critical acclaim as one of the best action films of its decade.

"Fallout" also stands out for being the first film in the franchise to bring back a director, Christopher McQuarrie, for a second consecutive installment, building directly on the events and characters from the previous film, "Mission: Impossible - Rogue Nation." This continuity allowed for deeper exploration of Ethan Hunt's character and the consequences of his unwavering commitment to saving lives. The film was a massive box office success, becoming the highest-grossing entry in the series worldwide.