Setting in a misty park in London where the assassins meet someone at a boat

The movie is about an assassination attempt at the top of Big Ben. The person who try’s to stop the attempt gets framed multiple times for murder, and in the middle he comes out of a forest after being hunted to find a hunting party where he hides with them and goes to there house for the evening but the news talks about a murder in the woods he came out of so he had to leave. At the end the assassination attempt fails at the top of Big Ben and they bring a female hostage onto a boat where they try to escape