In the 2011 movie David Tennant played Las Vegas showman and vampire expert Peter Vincent.
In this video Charley (played by the late Anton Yelchin) pretends to be a reporter to approach Peter for help in killing the vampire named Jerry who lives next door to him.
Warning this video contains strong language and the video is short in accordance with the copyright holder's wishes.
Apologies if this video does not play in your country. Many thanks to the YouTube account Just Tennant for uploading the video.
Fright Night section of DavidTennantOnTwitter.com