Believability. Not all movies need it, but those that are attempting to depict realistic events do. The Sentinel, starring Michael Douglas, Kiefer Sutherland and Eva Longoria does well on this count, almost all the way through the film.

Douglas is Pete Garrison, a US Secret Service agent on the Presidential detail who once took a bullet that saved Ronald Reagan's life. But when an agent is murdered and it is discovered that there is a traitor within the service, Garrison fails a polygraph and becomes the prime suspect though he insists he is being framed. Enter Jack Bauer as a Kiefer Sutherland who has remembered how to dress decently since his last shoot on the '24' set. Agent David Breckinridge is a loyal, by the book company man who does everything properly and is the lead investigator, with a rookie field trainee played by Eva Longoria, who doesn't do very much more than show up for her scenes. Such is the recipe for a snappy spy movie that excels in the believability column.

Until they get to Toronto.

The President is attending the G8 at Toronto City Hall, and this is where the assassination attempt will take place. First, the real mole in the service (who may or may not be Garrison, I'm not telling) decides to stand up to the terrorists and says that he won't go through with it, and he doesn't care if they expose him or kill him: checkmate! But this man apparently hasn't seen many movies, because he is flabbergasted when the bad guy takes out three pictures of his family and says, "Oh, we're not going to kill you, we're going to kill her, them, and her."

Then the summit begins, and the American President gets up to the podium and says, "We must ratify the Kyoto Protocol." Righhhhht. They cut to the streets where a big angry mob is attacking police and storming the barricades: are we sure that this is supposed to be Toronto? And finally the attempt is made, in the stairwells of City Hall no less, by assassins dressed in Canadian military fatigues complete with bright red maple leafs on their shoulders.

For all you screenwriters out there, please do your research.