London — Among London's most famous and enduring sights are the sparkling marquees, colorful posters, and Victorian interiors of the city's 46 traditional theaters. In recent years, the story behind the footlights has been disturbing: falling attendance, spiraling production costs, and a strong pound sterling against most currencies keeping the number of tourists down.
This summer, the bad news has not entirely disappeared - but there is more to be hopeful about.
Even a year ago, 14 of the 46 marquees were dark. But right now, helped by a surge of American tourists taking advantage of a weaker pound vis-a-vis the dollar, only seven are still silent - and two of those hope to open up again before long.
''Not only that,'' says Vincent Burke, development officer for the Society of West End Theatre in an interview. ''We sold 5 percent more tickets in 1982 as a whole, a year in which cinemas were down almost 30 percent.''
American tourists, at least 12 percent more numerous this year, are particularly welcome these summer days, says John Barber, the theater critic for the Daily Telegraph.
With tongue partially in cheek, he adds, ''They stay longer, spend more, and buy more theater tickets than other nationalities because they think they understand the language.''
Eager to attract even more Americans in the fall and winter seasons this year , theater promoters are spilling out more good news.
* The restored Old Vic theater is due to open in October with a new Tim Rice-Stephen Oliver musical.
* Among leading performers stepping onto London stages later in the year will be Alan Bates, Judi Dench, Albert Finney, Michael Hordern, Penelope Keith, Glenda Jackson, John Mills, Ralph Richardson, and Richard Todd.
* Box office revenue (as distinct from the number of playgoers) shot up 20 percent in 1982 to almost $:59 million ($88.5 million).
And yet all is not entirely well behind those famous marquees.
''There are always the doomsayers predicting the demise of London theater, and there are always others saying everything is wonderful,'' Mr. Burke comments.
''The truth, however, still lies somewhere in the middle. We are now in the midst of a boom-ette, if you will, which we hope will encourage potential investors to come forward and enable more plays to be staged.
''But the problems remain: ever-escalating production costs and the obvious difficulties of raising money at a time of recession. . . .''
To these worries has just been added another.
Seven of the 46 theaters depend heavily on grants from the British government. They are facing significant losses of income because of Thatcher government cuts to the Arts Council, as well as in health, education, defense, and other areas.
The council has been ordered by Lord Gowrie, minister of state for the arts, to prune $:920,000 ($1.38 million) from its total grants to its 250 recipients in the current year.
The council is extremely upset: ''We resent and deplore being made to break our word to our clients in order to make good the overspending in other areas of government finance,'' said council chairman Sir William Rees-Mogg. The council's solution is to cut 1 percent from all its clients.
For the Royal Shakespeare Company, which is often called the most famous theater in the world, the news is bad, indeed. Deep in deficit despite an extra grant of $:850,000 earlier this year, it had been clinging to hopes that a government review, now under way, would result in even more funds.
In London, others affected are the National Theatre, the Royal Opera House, the English National Opera, the Mermaid, the Royal Court, and the Open Air Theatre.
Artistically, John Barber warns, there is a price to be paid if attracting tourists is a priority: ''Noisy spectacles with a major impact on the senses and a minimum appeal to the mind or heart.''
Yet London continues to burst at the seams with good theater, from Tom Stoppard's ''The Real Thing'' and the National's revival of ''The Rivals,'' to Michael Frayn's ''Noises Off,'' several thrillers, and the RSC's ''Tartuffe'' by Moliere.