Indiana Jones and the Kingdom of the Crystal Skull ending explained

What happens

At Akator, the skull is returned to its alien owners. Spalko is overwhelmed by their knowledge and destroyed, and the temple collapses as their saucer departs. Indy, Marion and Mutt escape, and Indy and Marion finally marry.

The last image

Mutt reaches for Indy's fedora at the wedding, but Indy takes it back and puts it on his own head.

What it says

Indy gets his family, but not a retirement. The hat shows Mutt is not handed the legacy yet. Spalko wanted knowledge to own, while Indy gives it back and is left with people instead of treasure.