IN CINEMA LAND, the line between fantasy and reality is particularly thin and fragile, like a strip of celluloid viewed edgewise. Movies are supposed to imitate life, but they merely imitate other movies. If you doubt this, try counting the number of times Shane, The Front Page or The Maltese Falcon have been rehashed. It's often left up to reality to conform to the images we see on our movie or TV screens, sometimes in very perverse ways.

A case in point: last Friday the Orson Welles Theater, one of the few class cinemas left, burned down. Even though the owner plans to reopen the theater sometime next fall, the Boston area will sorely miss the many special events, festivals, and obscurities that have been scheduled at this 17-year veteran of the Boston screen scene.

As the press sifted through the facts of the case, some disturbing clues began to emerge. Guess what films happened to be playing when the place went up in smoke?

Water. And Always.

What set off the fire?

A popcorn machine.

It's been less than a year since Welles himself died. First the man. Then his theater.

WHILE I CANNOT claim the sleuthing skills of a Humphrey Bogart or a William Powell, it doesn't take too many viewings of Sherlock Homes Faces Death to recognize the tell-tale signs of some malevolent genius at work. Who could he be?

A homicidal maniac a la Mark David Chapman, out to erase all vestiges of the Master out of some perverse adoration of his work?

Some disgruntled Hollywood figure whom Welles had crossed in the past? Perhaps the old rumors are true, and the ghost of Herman Mankiewicz, Welles' undercredited collaborator on Citizen Kane, still walks among us.

Maybe the villain has no connection to Welles, and these dastardly deeds taken together make some sort of code, like in Borges' "The Garden of Forking Paths," which can only be interpreted by someone holding a key bit of information.

Alternately, the fire could have been engineered by some ruthless entertainment conglomerate bent on owning all of Welles property and destroying all that escapes its greedy clutches, a sort of "War of the Welles."

Whatever the real story behind the mysterious events at the Orson Welles last Friday, I would recommend extreme caution to anyone planning to see Jouney into Fear or A Touch of Evil in the near future. As for me, I have to go button my trenchcoat and don my snapbrim before I venture out on a lonely quest for a little truth down those dark, mean streets.

See you at the movies.