It's pointless to encapsulate the plot, because there isn't much of one. It punishes rather than entertains. It condescends, it offends, it loathes its audience. It treats us like infants who only want to see things blow up and catch fire because we're not smart or developed enough to handle genuine emotion or terror. When The Mummy Returns mints a fortune, we'll no doubt get a third installment in which all the actors are computer-generated, replaced by ones and zeros.
Audiences get what they deserve.