This year's Classic Thriller Season, the 23rd, is in honour of Colin McIntyre, the instigator who died three months ago aged 82.
The season can arguably rival cricket matches at Trent Bridge and the county council's Robin Hood Festival for must-see entertainment during the summer.
So why do audiences keep returning to the Theatre Royal year after year? That's because the four plays selected don't call for too much concentration on what can be a hot evening; they usually keep you guessing as to who's committed the foul deed; and there's a hint of humour thrown in - something which some authors might not have intended.
Sweet Revenge is a typical Classic Thriller Season play. Although you can see the murder approaching with all the subtlety of one of the trams which stops outside the Theatre Royal, you struggle to identify the killer before the dénouement.
Heart surgeon Ross Marquand's wife's lover is found dead in their living room one weekend when Ross has invited several people to a regatta. He's obviously in the frame, but most of the characters have a credible motive for bumping off Julian Kane - a serial womaniser who angers a few husbands as well as the women he dumps. He's also a bit of a loan shark.
Some of the characters actually think they killed Kane; that heightens the mystery and keeps you guessing right until the end.
Although Sweet Revenge - Durbridge's last play - was written in 1991, director Patric Kearns sets it in the 1970s. Unfortunately, though, the play is showing its age. It runs for under two hours - but at times, especially in the first act, it's a bit pedestrian. Nevertheless the company make a creditable job of it.
The main reason is that most of the actors have vast experienced of the thriller season; they know what audiences expect of them and they deliver the goods with only a slight hint of exaggeration and stereotype.
Ben Roddy as Ross towers over most of the cast yet his height helps him to have a dominant stage presence. He has authority and gravitas; you feel for him when he discovers his wife Fay has become infatuated with Kane and, if he's committed the murder, you can almost defend it as justifiable.
There are some familiar faces in the cast who've been in the Classic Thriller Season for several years yet each brings a freshness to his or her performance.
Jo Castleton as Fay gives her customary polished performance; Nicholas Briggs presents a weighty portrayal of Dr Sam Kennedy; and John Hester is solidly impressive as loyal Bill Yorke.
But Karen Henson gives a baffling portrayal of Marian Palmer - just what is that accent? - and Al Naed's Cockney copper is so clichéd it's as old as the hills.
Despite that, it's a sound start to the season. Colin McIntyre would approve.
The Classic Thriller Season continues with "Death by Fatal Murder" from 15th to 20th August, "Strangers on a Train" from 22nd to 27th August and "Murderous Liaisons" from 30th August to 3rd September