German historian Jan Tilman Schwab is the world's foremost academic writer on soccer films and the author of Fußball im Film – Lexikon des Fußballfilms ("Football in Films – Lexicon of Football Films").

K+S: What makes a film a “soccer film”?

JTS: In a narrow definition, the film would need to deal with football as its main theme/plot line. In a broader definition that I used for my lexicon, a film could also deal with soccer in an elaborate sub plot or even in its subtext (if stringent). As an example, Trainspotting has three brilliant soccer motives in its plot -- but not enough for me to call it a soccer movie.

K+S: What makes the game of soccer so good for film?

JTS: The passion for soccer can sometimes be transported to the screen, for as football fan and cinéaste it couldn't be better...

K+S: What are the best examples of a “soccer film”?

JTS: Zidane, as an art film, and Fever Pitch, as fan-fiction comedy at its best.

K+S: There are relatively few fictional soccer films. Why is it so difficult to make a good fictional soccer film?

JTS: The reproduction of soccer for a fictional film is difficult. You need good actors/footballers. You have to recreate an authentic big crowd. And you have to reproduce gameplay -- usually without a big budget and/or digital trick techniques. Altogether, this is hardly achievable.

K+S: If you could make a soccer film right now, what story would you tell?

JTS: A serial killer takes out one German referee after another... because they are screwing up my beloved Bayern Munich this season! No, all kidding aside, any good story that creates characters full of love for this sport who get into situations where they follow their passion encountering obstacles from the "real" world should work.

Jan Tilman Schwab, left, at the 11-mm Fussballfilmfestival in Berlin in 2013.