Magda, die lang geleden haar carrière heeft opgegeven omwille van haar gezin, woont in Podkowa Leśna, in de buurt van Warschau. Op een avond ontdekt ze bij toeval het lichaam van een vermoorde vrouw in het park. Ze heeft een W-vormige ketting om haar nek, identiek aan die van haar lang verloren gewaande vriendin, Weronika. Hoewel het officiële onderzoek geleid wordt door commissaris Jacek Sikora, een voormalige vriend van Magda die verliefd op haar was, besluit Magda als dwangmatige lezer van misdaadfictie zelf op onderzoek uit te gaan.
Ja! de film W jak morderstwo is nu beschikbaar om te kijken op Netflix in Nederland.
| Directing | Piotr Mularuk | Director |
| Directing | Barbara Burska | Assistant Director |
| Editing | Agnieszka Glińska | Editor |
| Sound | Paweł Lucewicz | Original Music Composer |
| Production | Nadia Lebik | Casting |
| Production | Kacper Habisiak | Co-Producer |
| Production | Piotr Mularuk | Producer |
| Camera | Adam Bajerski | Director of Photography |
| Writing | Katarzyna Gacek | Writer |
| Writing | Piotr Mularuk | Writer |
| Writing | Katarzyna Gacek | Novel |
| Camera | Krzysztof Szulim | Grip |
| Camera | Marcin Brzezek | Grip |
| Lighting | Maciej Chmielewski | Master Lighting Artist |
| Editing | Michał Krajewski | Digital Intermediate |
| Camera | Romuald Lewandowski | Camera Operator |
| Camera | Łukasz Zygmunt | Grip |
| Directing | Konrad Bajno | Assistant Director |
| Camera | David Bajerski | Camera Operator |
| Camera | Adam Bajerski | Camera Operator |
| Sound | Michał Bagiński | Sound Director |
| Sound | Filip Krzyżykowski | Sound Effects Editor |
| Production | Aleksandra Cyganek | Production Manager |
| Art | Marcin Łakomy | Props |
| Crew | Paweł Latos | Stunts |
| Sound | Kacper Habisiak | Sound Director |
| Costume & Make-Up | Zuzanna Zakrzewska | Assistant Makeup Artist |
| Crew | Piotr Wojtkowski | Stunt Coordinator |
| Crew | Aneta Kielak | Catering |
| Sound | Kacper Habisiak | Sound |
| Crew | Nathaniel Espino | Translator |
| Production | Aleksandra Orzechowska | Production Coordinator |
| Art | Natalia Giza | Production Design |
| Art | Jakub Kaleta | Assistant Production Design |
| Art | Magdalena Dymińska | Assistant Property Master |
| Costume & Make-Up | Weronika Pietrzak | Costume Assistant |
| Costume & Make-Up | Marta Tesche-Klimek | Makeup Department Head |
| Costume & Make-Up | Ewelina Krzywda | Hairdresser |
| Crew | Karol Zagórski | Public Relations |
| Costume & Make-Up | Julia Ślusarczyk | Costume Assistant |
| Crew | Aleksandra Karbowiak-Dajewska | Public Relations |
| Production | Agata Sieradzka | Assistant Production Manager |
| Costume & Make-Up | Emil Wysocki | Costume Assistant |
| Crew | Aleksandra Misiak | Public Relations |
| Sound | Miłosz Jaroszek | Sound |
| Crew | Tomasz Kędzior | Stunts |
| Crew | Wojciech Konkol | Health and Safety |
| Crew | Ryszard Kluza | Catering |
| Art | Jan Kołodziej | Assistant Production Design |
| Art | Konrad Krysiak | Assistant Property Master |
| Crew | Mirosław Pisarek | Stunts |
| Crew | Julia Bui Ngoc | Choreographer |
| Crew | Paweł Kowalski | Stunts |
| Art | Marcin Gloeh | Assistant Property Master |
| Sound | Ewa Wrzesińska | Dialogue Editor |
| Crew | Marcin Kurowski | Public Relations |
| Crew | Agnieszka Pawłowska | Stunts |
| Crew | Karolina Pilarczyk | Stunts |
| Crew | Michał Basiński | Catering |
| Costume & Make-Up | Zuzanna Żurawska | Costume Assistant |
| Crew | Joanna Jakubik | Public Relations |
| Visual Effects | Filip Kaczorek | VFX Supervisor |
| Art | Daniel Feliński | Assistant Property Master |
| Art | Sebastian Glinicki | Assistant Property Master |
| Editing | Jason Merle | Assistant Editor |
| Camera | Desi Kunsa | Still Photographer |
| Crew | Zbigniew Modej | Stunts |
| Art | Mikołaj Makulski | Assistant Property Master |
| Art | Piotr Furman | Assistant Property Master |
| Costume & Make-Up | Dorota Roqueplo | Costume Design |
| Crew | Bartłomiej Kowalski | Acting Double |
| Production | Andrzej Hajdaniak | Co-Producer |
| Production | Marcin Kasiński | Co-Producer |
| Crew | Ewelina Pawlus | Script |
| Production | Michał Krajewski | Co-Producer |
| Production | Kamil Rutkowski | Co-Producer |
| Production | Jolanta Surgiewicz | Accountant |
| Production | Agnieszka Sieradzka | Producer |
| Production | Agnieszka Sieradzka | Executive Producer |
| Production | Alois Rostek | Co-Producer |
| Production | Krzysztof Gawrysiak | Co-Producer |
| Production | Maciej Mika | Co-Producer |
| Production | Tomasz Grzybowski | Co-Producer |
| Art | Maciej Mika | Main Title Designer |
