Roddy McDowall has been making movies since Lassie was a pup and Elizabeth Taylor an innocent teenager - working with them both when he was 12.

The English-born McDowall, 60, has enjoyed an extraordinary longevity on movie screens despite some ups and downs and even a hiatus from Hollywood when he was 17 and could not find film work for six years. All the same, he has appeared in 110 movies.While he was never a name-above-the-title star, McDowall recently found a vehicle that has made him a major box-office attraction: "Fright Night."

The horror film was so well received - $35 million domestic gross - that he is starring in the sequel "Fright Night: Part 2." If the new version is as popular as the first, there may be subsequent "Fright Nights."

"The sequel is every bit as good as the first film," McDowall said the other day at a fancy San Fernando Valley restaurant. "And I hope there's a third.

"`Fright Night' is not your ordinary run of horror films. It's not a slasher-type film at all. Not a lot of gore and violence. It is full of hokum and laughs. There's a wonderful wit about it.

"We must not be confused with `Nightmare on Elm Street' or `Halloween' and the others. We are not a hard-core horror film."

McDowall plays Peter Vincent, an eccentric ex-actor who hosts a TV show featuring old horror films.

But Vincent once played the title role in "The Fearless Vampire Killer" and the neighborhood youngsters believe he can dispatch vampires.

McDowall is as much at home in horror films as he is with science fiction, Biblical epics, historical sagas and contemporary drama as he is with comedy.

He has covered the spectrum of roles from cabin boys, to Roman emperors, murderers, businessmen and victims.

McDowall is also no stranger to motion picture sequels, having starred in four of the five "Planet of the Apes" pictures.

"It is very unusual for someone to make a sequel that is not derivative yet maintains the essence of the original," McDowall said.

"Sequels have been with us almost since the beginning of time. Remember the `Andy Hardy' and `Maisie' series and `Dr. Kildare' and `Blondie and Dagwood.'

"We carry on with sequels like `Indiana Jones' and `Star Wars' and `Romancing the Stone.'

"From an actor's standpoint, sequels can be fun because it is nice to renew the acquaintance of a character you enjoy playing. That can be fun, but it depends on how the story is handled. It's no fun to be in a sequel if it has no quality.

"If the script is acceptable and the character is plausible, then there's every reason to continue. All the elements were in place for `Fright Night: Part 2' so I had no objection to doing it.

"Peter Vincent is a delight to play because he is a talentless actor. He's a coward and very lonely. But he's also very dear, a man of good character and good nature, but he's scared of his own shadow.

"I like to think of him as a wealthy character, filled with a variety of personality traits in conflict with each other.

"Peter is a bizarre character and those are the ones I like most to play. Like all actors I enjoy playing classical characters as I did in `Saint Joan,' `Misalliance,' `The Doctor's Dilemma,' `The Tempest' and `Compulsion.'

"By the same token, I loved playing Andy Griffith's sidekick in `No Time for Sergeants' on stage. The character was the first major American role I ever played. He was a unidimensional character, which is interesting to play when you've been doing very complex roles.

"Also, I loved playing the ape under all the makeup. You had to call upon a rather inventive acting mechanism to register through all that appliance. I wouldn't have acted the role the same way without all that slap-on.

"As an actor, provocative roles are always the most interesting and certainly the most challenging.

"Just two years ago I did a pilot for a TV show that never got on the air, playing an Asian karate master. It didn't make it to the air, but it's opportunities such as that that keep one's hopes alive."