Lewis stars Kevin Whately and Laurence Fox are to bow out of the popular crime drama after nearly 10 years on air.
ITV confirmed Lewis will end with a two-part film titled What Lies Tangled. The first part will be broadcast on Tuesday, and it will conclude next Tuesday.
Whately said: "I feel incredibly fortunate to have shared a decade of fantastic worldwide success with Laurence and with the most brilliant crew, cast and production team anyone could wish for, and all that time with the loyal support of so many fans and of our backers ITV and WGBH Boston. Thanks everybody. What a ride it has been!"
The Northumberland-born actor first played the role of Lewis in 1987, opposite the late John Thaw in ITV drama Inspector Morse.
Spin-off Lewis premiered in 2006 with Fox - a member of the famous acting dynasty that includes his father James, uncle Edward and cousins Emilia and Freddie - as James Hathaway.
Set five years after the death of his long-term partner Morse, Lewis found himself teamed up with a much younger partner, and reporting to a new boss in the form of Chief Superintendent Jean Innocent (Rebecca Front).
Fox said: "What an extraordinary 10 years. I feel so lucky to have worked with absolutely the best crew in the business on Lewis. I will really miss hanging out with Kev for half the year. I am however fairly confident that he will not miss my flawless Geordie accent between takes. Thank you so much for watching and supporting us."
What Lies Tangled, written by Nick Hicks-Beach and directed by David Drury, opens with an idyllic Oxford summer day being blighted by a parcel bomb.
The victim of the attack is eminent mathematician Adam Capstone (Tristam Summers), a genius in the field of "knot theory".
With a six-month trip to New Zealand with pathologist Laura Hobson (Clare Holman) fast approaching, Lewis fears what will happen if he does not impress Chief Superintendent Joseph Moody (Steve Toussaint).
Lewis is in a race against time not only to find a killer, but also to save his career and his relationship.
The final episode also includes series regular Angela Griffin as Detective Sergeant Lizzie Maddox.
Executive producer Michele Buck said: "To have produced the same amount of films as Morse is an honour. I will miss Lewis."
ITV's director of drama Steve November said: "It is with great sadness that we say goodbye to Robbie Lewis, one of ITV's most loved and enduring characters. We owe Kevin a huge debt of gratitude for nearly 30 fantastic years of Morse and Lewis, and, of course, many thanks too to Laurence Fox who has been by Kevin's side for the last 10 years.
"We respect their decision not to continue into a further series and wish them the very best for whatever comes next."