Frank Bullitt (Steve McQueen) is a Lieutenant whose team is charged with protecting what they are told is a Mafia informant for an important in-the-public-eye trial (by an ambitious upstart politician Chalmers (played by Robert Vaughan)).

The guy being watched undoes the chain on the door and is shot when two men enter, Carl, Bullitt's colleague, is shot too.

They are taken to hospital and the assassin turns up again. Bullitt finds out he is in the building and gives chase but then loses him. The watched guy dies anyway, but Bullitt seeks to hide the body, fearing there is something wrong.

He is followed by the assassin, turns and gives chase in classic scene through streets of San Francisco and then into the outskirts of the city where the assassin (a passenger in the car) shoots at Bullitt. The bad guy's lose control of the car and end up blowing up a garage.

"At the time it was simply wonderful to see such a glamorous chase through the streets of San Fran. Today's audience will be disappointed as it has been done many a time on the Playstation. Still, not a terrible couple of hours spent, if just to chortle at the late Sixties fashions."

"It reminded me of the time I drove through San Fran just last month - I got sparks too, my dear, a delightful memory jog and I'm in my 90's!"

"Hollywood realism peppered with a few unrealisms to keep the pace up. A triumph, although to the modern eye a little boring in places."

"No high kicking or punching, just shooting and talking calmly and then making the bad guy lay with a surprised look on his face in ketchup, now that's realism."

"This movie is very dated now, to me it looked like a very good episode of TV's Streets of San Francisco, but without the epilogue at the end."

"I am a West Wing fan: isn't that a dapper younger Leo in there alongside Mr McQueen?"

It is discovered that the man they were sent to watch is the wrong man. Bullitt is told the right man is about to escape, by plane, to Italy.

The bad guy switches planes to London. The plane is stopped and evacuated. He runs when he sees Bullitt, and temporarily escapes, but then gets shot when he can't get through the airport exit...