He's back and he has a funny feeling about this...
It is 1957 and ten years later than "... And The Last Crusade." However, "...The Last Crusade" was released in 1989 and Harrison Ford is now 65, and you do the math. On the other hand, we last saw Marion Ravenwood in "...Raiders of the Lost Ark" in 1936, and sometime before they broke up before they were to get married, Marion gets pregnant and hen later married Orville Williams 3 months after her son was born.

Mutt needs Indy's assistance to help his mother Mary Williams who was kidnapped and taken to Peru.
Needless to say, this Indiana caper takes place up in the Andes, and the opening scenes take place in Area 51.
Outside the MP outpost, you see a diner, "Atomic Cafe." There could be a real Atomic Cafe in Nevada, but any flm student from the 70s and 80s knows that this sign is from Nancy's Atomic Cafe in Little Tokyo. I think the sign is with the Neon Museum in Los Angeles. George Lucas and Frank Marshall and friends may have eaten at this 24-hour cafe.
Indiana is taken to a warehouse to find something he left there years ago. No, it's not the Ark of the Covenant, however, the Ark does show up in the ensuing chase around the secret military warehouse.
Our hero finds himself in a test blasting site for an atomic bomb, and runs into a fake 50s town. I didn't check to see the license plate of the bel air convertible to see if it reads THX 338 - but it did have a resemblance to the one used in "American Grafitti."
Strangely, Indy speaks Mayan, even though the location is clearly Incan. But in the storyplot, they could be related.
The film is exhausting as it reaches its climax. It exsplains everything and nothing, as you shall see in its storyplot.
Before the film, Indy had lost his father, Henry Jones, and the College President, from the earlier films.
And should "Mutt" or Henry Jones III come back to take on the new adventures? Why not?
Knowledge is treasure.