plot point, counterturn, twist of the knife, coup de théâtre, change-up, thriller, coup de theatre, handbrake turn, catastrophe, deathtrap, more...

predictable, cliche, overused

unexpected reveal, mistaken identity, time loop, unreliable narrator, hidden motive, false memory, parallel universe, dream sequence, more...

story surprise,   cinematic twist,   literary twist,   a twist,   unexpected twist,   unexpected turn,   twist in the tale,   story subversion,   twist as in a movie,   an unexpected twist