Foyle's War will be over after this weekend, with ITV announcing that the long-running series will air its last ever episode on Sunday.
Michael Kitchen has played MI5 senior intelligence officer Christopher Foyle since the drama began in 2002 and will bow out with the rest of the cast in creator Anthony Horowitz's finale, Elise.
Foyle's last case sees him investigate Hilda Pierce's (Ellie Haddington) top secret role in the special operations executive during the war, after someone attempts to assassinate her outside of MI5. He suspects it may be to do with the hunt for a traitor in the department who could have been responsible for the deaths of nine agents in France.
During its run on ITV, Foyle's War has taken in the start of World War II, the Blitz, VE Day, the Cold War's secret intelligence, Soviet spies and the atomic bomb.
Its storylines over 24 two-hour episodes have also taken in developments such as plastic surgery and the invention of radar.
Anthony said: "It feels a terrible wrench to say goodbye to characters I've lived with for more than 15 years. But the truth is that I'm not sure there are any more stories to tell and anyway it was always my intention to end on a high note and I think this year's episodes are the very best we've done.
"I'm proud of what we've achieved with Foyle's War and I'm very grateful to the audience that has stayed with us for so long. I've had a good war."
ITV's director of drama Steve November added: "We are very sad to be saying goodbye to Foyle's War after so many amazing years, but delighted that the finale is so rich and mesmerising.
"Christopher Foyle has been a classic ITV hero and we are indebted to Anthony Horowitz for creating him and writing so many original stories for him, to Michael Kitchen for bringing him to life so brilliantly and to Eleventh Hour Films for consistently impeccable production."
The final episode will also include cast regulars Honeysuckle Weeks, Daniel Weyman, Tim McMullan and Rupert Vansittart, and will air on ITV on January 18 at 8pm.