Kenneth Branagh

 Kenneth Branagh was aware of the over-extravagance of his mustache when he played Hercule Poirot in "Murder on the Orient Express" (2017), but he justified it by the fact that there were fifteen quotes in the original Agatha Christie novel mentioning the mustache. When the trailer was first released, many Christie fans complained about Branagh's interpretation of Poirot's iconic mustache. When the book was first adapted for the screen in 1974, Christie, who was still alive at the time, was reportedly unhappy with Albert Finney's Poirot's mustache. Branagh admitted that he tried but was unable to grow out a full mustache for playing Poirot.

Much of the cast and extras are made up of Branagh's closest friends and acquaintances, with many of them having either been directed by Branagh in his previous projects, co-starred with Branagh in a movie or theatre production, and/or have been a member of Branagh's eponymous theatre company.

Branagh had the cast film their "interview" scenes on each actor's or actress' first day in order to capture the "first day excitement". Michelle Pfeiffer, whose first day on-set was the scene in which her character Mrs. Hubbard reports to Poirot that there had been a man in her room, loved the idea, while Penélope Cruz greatly resisted it.

According to Branagh's autobiography, "Beginnings," it was seeing Derek Jacobi play Hamlet onstage as a boy that convinced him to pursue acting.Branagh and Derek Jacobi appeared together in "Henry V" (1989), "Dead Again" (1991), and "Hamlet" (1996), and this film.. Branagh also directed Jacobi in "Cinderella" (2015).

Johnny Depp asked director Branagh to apologize to Jacobi on his behalf after filming their scene together "because I had to shout at him, I don't want to shout at Derek Jacobi."

Happy Birthday, Kenneth Branagh!