Vlassov is een Sovjet-spion die overloopt in Frankrijk. Hij wordt naar de VS gebracht, waar Allan Davies de zaak overneemt. Na polygraaftests en kruisverhoren noemt Vlassov verschillende West-Europese agenten die ook voor de Sovjets spioneren. Davies wil de genoemde agenten in hechtenis nemen; Ondertussen beginnen degenen op de lijst onder mysterieuze omstandigheden te sterven.
Nee, helaas is Le Serpent nog niet beschikbaar op Netflix in Nederland.
| Directing | Henri Verneuil | Director |
| Writing | Gilles Perrault | Screenplay |
| Production | Henri Verneuil | Producer |
| Sound | Ennio Morricone | Original Music Composer |
| Writing | Henri Verneuil | Screenplay |
| Camera | Claude Renoir | Director of Photography |
| Directing | Lucile Costa | Script Supervisor |
| Camera | Charles-Henri Montel | Camera Operator |
| Camera | Vincent Rossell | Still Photographer |
| Sound | Jean Rieul | Sound |
| Directing | Marc Grunebaum | First Assistant Director |
| Editing | Pierre Gillette | Editor |
| Costume & Make-Up | Hélène Nourry | Costume Design |
| Art | Jacques Saulnier | Production Design |
| Writing | Pierre Nord | Novel |
| Production | Jean-Pierre Nossereau | Location Manager |
| Costume & Make-Up | Marie-Madeleine Paris | Makeup Artist |
| Production | Jacques Juranville | Production Manager |
| Costume & Make-Up | Jean-Pierre Eychenne | Makeup Artist |
| Editing | Catherine Ganz | Assistant Editor |
| Production | Jean Drouin | Unit Production Manager |
| Editing | Nadine Muse | Assistant Editor |
