Have you ever read a one-line movie description before you read the title and assumed it was another movie? A recent Ask Reddit thread posed the question: “Which two unrelated movies can be summed up with the same sentence?” Summing up a film in only one sentence makes it overly simple, and only highlights that we have very few types of stories, and they are told over and over. The pair above can use the line, "A Bitter Old Man Loses His Wife, Befriends His Young Asian Neighbour Who Helps Him Overcome His Bitterness And Cyncism." That's pretty detailed. However, it's not only a similar plot that can be used this way- sometimes it's a joke. The line for the movies below is "A Bunch Of Dinosaurs Kill A Lot Of People."
See 47 pairs of films that have nothing in common except the one-liner that describes them at Bored Panda, and read the original reddit thread here.