A poster for ‘Indiana Jones and the Kingdom of the Crystal Skull’ has been revealed, and some details from the well kept secret plot are also out.
Indiana Jones co-producer Frank provides some detail around the story, which is about a quest for South American relics with supernatural powers.

The Last Crusade, was set in 1938 near the start of World War II, while the new movie, due out this spring, jumps over to the height of the Cold War in 1957, so the character has aged in real time â?? 19 years (while Harrison Ford is now 65).  So Indy like the actor that plays him will show his age and will be racing for the Crystal Skull against operatives from the Soviet Union now, including Oscar winner Cate Blanchett as the seductive Agent Spalko.

Beowulf star Ray Winstone, co-stars as an unethical rival archaeologist, while Transformers star Shia LaBeouf sports greaser hair and rides a motorcycle as the hero’s sidekick.

Crystal Skull will revisit bits from other Indiana Jones films, including Karen Allen’s feisty Marion Ravenwood from 1981’s Raiders of the Lost Ark.

The artifact of the title ‘Crystal Skull’ is inspired by real quartz sculptures of disputed origins that are carved in a way that defies the natural structure of the crystal.

Source