Saruman won't show until the second movie, as a connection between both stories. At this point in the timeline, Saruman was starting to think of the One Ring and it's whereabouts, due to the fact he had come in possession of a Palantir. Sauron, through Saruman's Palantir, started to intercept his thoughts and feelings, changing Saruman's side slowly but surely. Right before the LotR's timeline begins, Saruman's holds a gathering with the Istari to bring the Ring's whereabouts back up. He tells the council he believes the Ring has traveled out to sea and will never be returned. He secretly starts a search party and starts banding together orcs, to make Isengard a stronghold. His allegiances in the Hobbit timeline are beginning to slightly sway, though he is still a council member and advicer-giver to Gandalf and the rest of the Istari.
Now, Radagast lives out in the wild and frequently visits with Gandalf, as he is one wizard lower. He gives Gandalf valuable information about the goings-on in wild and conversations he has over heard whilst out and about. He may or may not show his head in the first movie, as they travel over the Misty Mountains, before they meet with Beorn.
