Olympus Has Fallen starts off introducing the characters with a little bit of backstory. I won't go into detail but it seemed that it was designed just for the emotional kick in gut than something that contributed to the story. Once thats done we move to the present time and the movie kicks off.
Mike Banning (Gerard Butler), a Secret Service agent, is working across from the White House when the unthinkable (and unbelievable) happens. An attack compromises the Whitehouse and forces the President to seek shelter in an underground bunker with a foreign prime minister. Unbeknownst to everyone is that the foreign prime ministers guards are in on the attack. Mike takes it upon himself to wade into the battle and save the day.
Parts of the movie really stretch believability to it's limits. While other sequences are grounded in reality. Overall it makes Olympus Has Fallen really enjoyable. Once the action starts it doesn't stop. You will be on the edge of your seat until the end.
As far as action flicks go, this one is much better than the last. But there are some confusing and distracting elements in the plot that detracts from the overall movie. Another thing I expected was a bit more humor. Compared to the last movie Retaliation was all business.
For the action scenes alone I would have given this movie 4 stars, almost 5. But the side plots interrupted the flow of the movie without contributing in a meaningful way.