its more a comical farce...first off, roger thornhill is too erudite to be miffed by the crooks, so he's playing along for his own amusement...its way too funny and it tires me to see such effort wasted...grant is having fun with this role and milking it for all its worth....eva marie saint saves this film from disaster ...and just in time...after all, alfred was the master of timing...i knew it was going to be funny when in his cameo role the bus driver shut the door in his face
There are a lot of one-liners in North by Northwest, and some great physical gags(like Grant's early drunk act), but the film artfully weaves the humor into a story that is dead serious in the consequences:
It becomes pretty clear that Vandamm and his men are only interested in one thing: killing Cary Grant. And they have killed several REAL CIA agents before he stumbled into their plot. And they kill the UN diplomat. And they are ready to kill Eva Marie Saint at film's end.
In short..and particularly for 1959...this is a ruthless band of men who prefer to kill their problems. The knife-throwing brute Valerian is particularly nasty. Cary Grant's Thornhill is in real danger, start to finish, and the jokes just leaven the suspense.
Which is exactly why this IS a Hitchcock thriller. The humor is key, but so is the suspense. He knew how to mix the brew.
Hitchcock would return to this mode one film later with "Psycho," in which horrible things happen but there are lots of little jokes along the way.
Familiarity with a film can change your perspective. I remember going to see NNW on campus with my college roommate many years ago. I had already seen it a number of times; he was seeing it for the first time. I told him it wasn't that terribly suspenseful a film, but that it had great entertainment value. After the film ended, he told me I was crazy, that his shirt was drenched with perspiration. I had forgotten what it was like to watch it for the first time!
Grant moves beyond playing it for laughs when we reach the last act. He begins to take things a bit more seriously after the auction and mostly stops clowning around once we get to Rushmore.