Lancaster, Rains, Henreid, and Lorre. All provide excellent performances but the plot is meh. It is shapeless. They tried Casablanca but ended up with a mess. Also there are a couple of scenes that feel like continuity errors, especially during the fight in the sand.
There is no denying that Dietrele was a gifted filmmaker. For the most part, however, he was a gifted director of what might generously be called middling material. Worked a ton. Reliable dude. And we have some supreme acting wattage on display here: Burt Lancaster, Claude Rains, Pete Lorre. Shazam! However, we also have Corinne Calvet giving what has to be one of the most comically awful performances of the era.