Visible crew/equipment: When the lizard gets away, and is riding in the elevator, it is shown alone in there. In the next shot from the back of the lizard, you can see the shadow of the handler or crew-member's head moving around on the top of the lizard.
Factual error: There are multiple mistakes in the Italian passport for Clark. Febraio (February) is spelled with only one 'b', and the city Palermo is followed by the region name, which is not put on a passport.
Continuity mistake: About five minutes before it ends,Bruno Kirby is sitting down at a table talking to Maximillian Schell and others. He loosens his tie, which lays to his right. The camera cuts away from him, then back to him, and his tie is on the left.
Plot hole: When Carmine tells Clark about the job he wants him to do, he tells Clark to deliver a package for a "Larry London." Once at Larry's home, they are greeted by Edward, who lives with Larry. Clark and Steve introduce themselves and ask if he is Edward, to which Edward replies he is. Only problem is Edward is never mentioned by Carmine or anyone else, so how do Clark and Steve know about Edward? (00:20:00)
Continuity mistake: The Italian social club's outside facade looks nothing like the inside of the building. There are many more windows in the inside view for instance.