After Charade became a big hit Stanley Donen tried to recapture lightning in a bottle with Arabesque. Gregory Peck seems ill at ease in a role I can only assume was written for Cary Grant. His partner is Sophia Loren. Unfortunately they don't have much chemistry.
Again it's a Hitchcockian pastiche, filmed with some 60s psychedelic touches, the story taking place in London rather than in Paris and the macguffin being a cipher that needs to be decoded. Someone is killed, the trace leads to Peck, so he's the innocent man on the run. There's also a chase to prevent the assassination of a prime minister, like in The Man Who Knew Too Much. It doesn't all make that much sense. Most of the dialogue falls flat. The villain could maybe have been a bit more camp.