Between them they have run up more than 100 years in the West End. All of them are still packed out. Yet none of them has set a major trend, or spawned imitators. These most frequented London shows are out on a WC2 limb.
Next month James Watkins's film of The Woman in Black will be released. For all the resources on which it can draw, for all that it stars Ciarán Hinds, Janet McTeer (I hope the stage has not lost her to the screen) and Daniel Radcliffe, the movie will find it hard to match the bounce-out-of-your-seat impact of the play. Ever since it opened more than 20 years ago, it has produced sounds – gasps, squeals, shudders, muffled screams – that are rarely heard in the stalls. Set in a misty Victorian East Anglia, it has glided effortlessly to Vienna and Australia, and translates particularly well in countries such as Japan and Mexico which have a strong tradition of ghost stories. The theatre – most fleshy of art forms – is remarkably effective at conveying the spectral. Watching this, with the deliciousness of shared fear, it seems amazing that so few attempts are made to scare audiences.
The genius of Stephen Mallatratt's adaptation of Susan Hill's 1983 novel is that it dares you not to believe in it. It doesn't try to mimic reality; it is diametrically opposed to the special effect. Set in a Victorian theatre, it has only two speaking actors, one of them shifting with the twist of a cap from one character to another. A props basket serves as a pony and trap and as the furniture for a house or office.
It is, like that other lovely potential long-runner The 39 Steps (five years old), a wonderful example of theatre technique on an austerity budget. It generates fear through simple surprises: in a deserted house a rocking chair creaks as if someone has just risen from it; behind a solitary figure a massive shadow steals along the wall. It magnifies fear by showing the terror on an actor's face: fright is contagious. It gives fear another dimension, for like all really good ghost stories The Woman in Black is grounded not in horror but in human pain and loss. The whole world, as contained in an auditorium, becomes threatening.
Not even a mouse would scream at The Mousetrap. Now in its 60th year on the London stage, and the longest running show in the world, Agatha Christie's play – thriller hardly seems the right word when even a corpse looks quite cosy – is visited in the same spirit that still sends tourists queuing at Lenin's tomb. It is a mummified relic of what was once believed in.
Which has a point of its own. The Mousetrap provides what a theatre museum, for all its perfectly preserved costumes, playbills and voice recordings, cannot. It gives audiences a chance to experience a piece of stage life lifted wholesale from the past, a piece that carries the DNA of the first performance, that has not been re-created but continuously re-enacted. Some of what is seen is the stuffiness that gives the overmaligned 50s a bad name, but it has a weird authenticity.
Here are chignons, tweeds, some fluting tones from the radio, a buttoned-up military cove, an alarming "spinster" and a fey young man with artistic inclinations. Over the years there have been various small attempts to update the text: these have sensibly now stopped. At one point the word "guineas" was excised; it is now back. At another, the epoch of the play, which its author described as set in "the recent past", was archly referred to as "Agatha Christie time". Now we know we are in the early 1950s.
Christie's biographer has pointed to the dark story of cruelty that triggers the plot, and a recent correspondent to the Guardian identified a relative as the real-life victim. Darkness and reality are scarcely apparent. What makes it still enjoyable, for all the creaks, are Christie's puzzle plotting, the soothing certainty of resolution, and one surprise that is never mentioned. The closing scene of The Mousetrap contains something that looks very like a joke. A wife presents her husband with a box of "splendid cigars". She does so with the earnest suggestion that he will smoke them. What else could he have had in mind?
Willy Russell's Blood Brothers, at the Phoenix since 1991, is a rousing theatrical success. It is as if Kurt Weill had written one of the best episodes of Corrie or (the late) Brookside.
Russell, author of Educating Rita and Shirley Valentine, has described Blood Brothers as the musical for people who don't like musicals. It runs against the genre, resisting a conservative tradition: set in Liverpool, championing an old-style working class, without a romance at its centre. Its most compelling character is a middle-aged woman; it has an onstage narrator, played with a Mephistophelean darkness by Marti Pellow, an austere aesthetic, a realistic social outlook and a sad ending – an ending that is revealed to the audience at the beginning, so that there isn't even suspense. It has, you might think, no right to succeed.
Yet in Mrs Johnstone, the strapped-for-cash woman who gives away one son and ends up losing two, Russell has created an unforgettable figure who is both luscious and besieged: a glowing-eyed dancer who likes to be compared to Marilyn Monroe, a mother of an ever-growing family "Living on the never-never, constant as the changing weather". The weird range of singers clamouring to act her – Carole King, Petula Clark, Barbara Dickson, Mel C, and currently the winning Amy Robbins – testifies to her power. The wit and grit of Blood Brothers may have helped pave the way for Billy Elliot and for Spend, Spend, Spend, Steve Brown and Justin Greene's musical about the pools winner Viv Nicholson, but there are few musical characters who measure up to Mrs J.
