Popular and dashing American singer Nick Rivers (Val Kilmer) travels to East Germany to perform in a music festival. When he loses his heart to the gorgeous Hillary Flammond (Lucy Gutteridge), he finds himself caught up in an underground resistance movement. Rivers joins forces with Agent Cedric (Omar Sharif) and Flammond to attempt the rescue of her father, Dr. Paul (Michael Gough), from the Germans, who have captured the scientist in hopes of coercing him into building a new naval mine.