Indiana Jones and the Kingdom of the Crystal Skull

The movie started with great promise and I thought I am going to enjoy it thoroughly. However, there comes the biggest disappointment at the end ... Warning: Spoiler ahead.

Aliens???!!! Flying saucer???!!! What crap! An alien that looks like E.T???!!! Is Steven Spielberg getting overly nostalgic? I expect an Indiana Jones movie to be exaggerated, stretch the imagination but aliens and saucers are simply too much. This film was in development since 1989 before the current script satisfied Lucas, Ford and Spielberg to produce the movie we see now. However, I am thinking if they are getting blocked in the head or just taking the audience for a ride.

Well, it seems the theme of Crystal Skulls was already in development years before. See this from Tokyo Disneysea. The attraction opened in 2001.