More than 10 years ago, I watched a vampire movie on a French TV channel and I have been searching for its title for 2 years now. I believe it is not a famous movie since I was not able to find anything.
There was a scene where the main hero (I think he was a vampire hunter, at least he was killing vampires in the movie, badass style), transfused the blood of a vampire to reduce his heartbeat and avoid being detected by other vampires, to be able to access their nest.
The final scene of the movie shows the hero driving and putting sunglasses as the rays of the sunrise were bothering him.
The scenes are blurred in my mind as it is just a childhood memory, for me now.