here and "Filming It" by me here. The latter links to a post about filming Mirkheim which links to a post about filming the introductory passage of "The Game of Glory." See also "Film Versions," here.
Although I welcome Sean's discussion of how to introduce films based on Poul Anderson's works, I think that the book blurbs that he cites are rather too wordy and "spoiler" for this purpose. The famous intro to Star Trek might serve as a model. Something about how mankind has spread into - rather than "through" - the galaxy would certainly make sense as an opener to any film or TV episode set in Anderson's Terran Empire.
However, I like my proposed start for "The Game of Glory," simply a narrator's voice quoting the opening sentence:
"A murdered man on a winter planet gave Flandry his first clue." See here.