Robert Aldrich once said he felt this film was disappointing not because it wasn't good but because it could have been good. He's dead right too - this has a simple basic idea that should have worked like a snap, but it's completely muffed: American journalist Robert Mitchum arrives in Athens before the German attack in 1941, gets a list of local resistance leaders to pass on to British intelligence, and spends the rest of the film trying to get it to safety.
That's a solid idea - a strong Macguffin, with a clear goal (get the list to safety), various people helping/hindering (local resistance, Gestapo agents, traitors, mistresses). Robert Mitchum's character is stock but effective - a selfish man who learns humanity. And there's some seemingly sure fire human interest such as the Germans executing Greek villagers who won't give up Mitchum, Mitchum falling in love with a Greek girl (Gia Scala) who dies, a double agent who's doing it all for her kids, a German with a conscience, some lively dodgy types who may or may not be on Mitchum's side (Sebastian Cabot, Theodore Bikel), plus location filming in Greece.
What went wrong? Well we never get much progression in Mitchum's character - he turns up in uniform so it's not clear he's a journalist, he doesn't seem that uncommitted at any phase. The macguffin keeps getting forgotten - Mitchum goes off on tangents like helping the Greek resistance in a raid on the Germans instead of getting the information to safety. It's never clear when the Germans come and occupy Greece (i.e. when the actual invasion has taken place and is completed). He spends this time on a romance with Gia Scala, which we invest in, then she's taken away and the second half of the film he has this relationship with Elisabeth Mueller, which we're meant to invest in as well. We hear Scala has been tortured and killed off screen; Mueller has these kids she loves but only see at the end.
Mueller and Stanley Baker have this potentially interesting relationship but in the final scene at the end when Baker lets her live, both are wearing stripy pajamas which are very distracting. The business of the list of Greek leaders is missed and indeed downplayed at times. And it's in black and white so the location photography isn't that effective. It's all a bit of a mess and it shouldn't have been.