NEW YORK — There is always an asteroid, real or imagined, bearing down on Turner Classic Movies .

Fears that something might befall the commercial-less bastion of classic Hollywood films aren’t always justified. But there’s an instinctual understanding that keeping anything good and pure alive in this dark, dark world is against the odds. By now, the hosts and executives of TCM are quite accustomed to fretful, agitated fans coming to them for reassurance that, yes, Turner Classic is OK, and, no, commercials aren’t coming.

“I’ve had the good fortune to get to know Paul Thomas Anderson a little bit and let me just put it this way: He never asks how I’M doing,” says Ben Mankiewicz, who in 2003 became only the second TCM host after Robert Osborne.

Almost everything in cable television and film has changed since Ted Turner launched the network in 1994. But through endless technological upheavals, four U.S. presidents and three Spider-men, Turner Classic humbly, persistently, improbably abides. On Sunday, TCM will turn 25, celebrating a quarter of a century as a lighthouse of classic cinema; a never-stopping, flickering beacon of Buster Keaton and Doris Day, Barbara Stanwyck and Ernst Lubitsch.

“We view ourselves as the keeper of the flame,” says Jennifer Dorian, general manager of TCM. “We’re stronger than ever.”

That will be good news to the TCM fans whose heart rates quickened after AT&T’s takeover of Time Warner, which had bought Turner Broadcasting back in 1996. That led to restructuring, announced last month, that placed TCM in WarnerMedia’s “global kids and young adults” subdivision, along with Cartoon Network and Adult Swim. WarnerMedia also shut down TCM’s nascent streaming service, FilmStruck , last November after deeming it a “niche service.” WarnerMedia is to launch a larger streaming platform later this year.