He winds up in a small hotel, where Matilda waits for her Navy boyfriend and a detective hunts Soviet informers. There are mistaken identities inside, and misguided nuclear tests outside in the desert.
Whittell also directs, competently enough, although a fresh eye might have suggested some judicious editing of a script overburdened by its considerable erudition.
Such streamlining would also have afforded the too-many themes - patriotism, forewarnings of McCarthy - more space.
Adrian Rawlins leaves an insoluble scientific equation where the character of Feynman should be, although Jennifer Higham has fun as the perky, feisty Matilda.
Corey Johnson's detective is imperiously laconic. But for better or worse, it's all about the writing.