It's actors who have played Batman, in chronological order. If there was a fifth it would be Ben Affleck.
It's the final word of the final four Harry Potter book titles, starting with the most recent, and going backwards. The next book is Harry Potter and the Goblet of FIRE.
These are the last three cities to host the Olympic Games – the next will be Tokyo in 2020.
It's the last four Republican presidents, in order. It couldn't have just been presidents in general, as it missed out Bill Clinton.
It's the four largest countries in the world by area, going from smallest to largest.
This is the line of succession to the British throne. Next in line is Charles, then his eldest child, William, then his eldest son George, so next would be William's second child, Princess Charlotte.
These are, obviously, the girls from the chorus of "Mambo No. 5". Next comes Tina.
If you arrange the countries in alphabetical order, these are the final four.
These are the movies, in order, for which Leonardo DiCaprio was nominated for Best Actor at the Oscars.
These are the first names of Henry VIII's wives, in chronological order. First there was Catherine of Aragon, then Anne Boleyn, then Jane Seymour, and so the next one would be Anne of Cleves.
These are the first four books of the Old Testament in reverse order. The first book is Genesis.
These are the Star Wars movies from Episode V onwards. Episode VIII will be released later this year, and is called The Last Jedi, so the answer should be "VIII TLJ".
These are the things desired by the four main characters in The Wizard of Oz, in the order in which we meet them. The next character is the cowardly lion, who desires courage.
These are the Prime Ministers of the UK, from the start of the Second World War onwards. After losing an election to Clement Attlee in 1945, Churchill returned to power in 1951.
These are the debut movies of the last four actors to play James Bond. Live and Let Die was Roger Moore's first movie, The Living Daylights was Timothy Dalton's, GoldenEye was Pierce Brosnan's, and then the most recent was Daniel Craig's debut, Casino Royale.
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