Compared to the Brendan Fraser helmed 'Mummy' films, the Tom Cruise version is a bit more energy but a lot less fun, especially since things get clogged in lots and lots of 'world-building'. This is meant to be not just a stand-alone movie but a focal point in a glitzy, highly-promoted franchise. And it really shows. One of the few things that works in the movie, if not the best thing in it, is the portrayal of the titular mummy. This villain is a cruel, remorseless monster trying to take the world, and she's played menacingly well. Those special effects with the mutated eyes will stay in your memory for a while.
Still, though, while it's nice to see Cruise fighting the supernatural, and a bunch of scenes have some legitimately great funny moments, the overall movie feels painfully average. The mishmash of a story-line is ultimately what drags things down the most. It's still worth seeing, but don't expect something particularly interesting or new.