Paul Reubens, the comic actor whose childlike alter-ego Pee-wee Herman became a movie and television sensation in the 1980s, and whose career was briefly derailed by a sex scandal in the early 1990s, died on Sunday. He was 70.

His death was confirmed on Monday by his longtime representative Kelly Bush Novak, who said he had “privately fought cancer for years with his trademark tenacity and wit.” He died at Cedars-Sinai Medical Center in Los Angeles.

Mr. Herman had scores of acting credits in a career that began in the 1960s, including roles on “Buffy the Vampire Slayer,” “Murphy Brown,” “The Blacklist” and many other television series and in movies like “Batman Returns” (1992) and “Blow” (2001). But Pee-wee, a character he created in the late 1970s as a 10-minute bit when he was a member of the Los Angeles comedy troupe the Groundlings, overshadowed all else, morphing into a bizarre and savvy cultural phenomenon, a character aimed (at least in its TV incarnation) at children but tapping into adult sensibilities and ambiguities.

After being disappointed after auditioning unsuccessfully for the “Saturday Night Live” cast in 1980, Mr. Reubens set about creating “The Pee-wee Herman Show,” which was billed as a “live onstage TV pilot” and had its premiere in early 1981 at the Groundlings Theater in Los Angeles. A national tour followed, and in 1981 HBO broadcast a version of it as a comedy special.

Pee-wee started turning up on late-night talk shows, especially “Late Night With David Letterman,” where the juxtaposition of the idiosyncratic Pee-wee’s and the laid-back, somewhat befuddled Mr. Letterman was comedy gold.

Then, in 1986, came “Pee-wee’s Playhouse,” a children-friendly version of the world according to Pee-wee that aired on CBS for five years and carved out an enduring place in the memories of 1980s children and, often, their parents.

“Pee-wee’s Playhouse” stands as one of the oddest, most audacious, most unclassifiable shows in television history. The androgynous Pee-wee and a vast collection of human and nonhuman characters — there was, for instance, Chairry, a talking armchair that gave hugs — held forth in each episode about, well, it’s hard to summarize. There was a word of the day. There were bizarre toys. In one episode, Pee-wee married a fruit salad.

The show arrived in the midst of Ronald Reagan’s presidential administration and harked back to another button-down era, the one Mr. Reubens lived as a child: the 1950s.

Laurence Fishburne, S. Epatha Merkerson and other actors of color were in the cast. Gilbert Lewis, who was Black, was the King of Cartoons.

The show was a world away from standard educational TV for children, its lessons — if any — delivered through wackiness rather than didactically, and its presentation decidedly nonlinear. It wasn’t ;ong before academics and cultural critics were analyzing it and its appeal with weighty papers and other commentaries, but Mr. Reubens was having none of that.

The wheels came off in July 1991, when Mr. Reubens was arrested on a charge of indecent exposure in an adult movie theater in Sarasota, Fla., where he had grown up. The arrest led to a small fine, but the headlines damaged his reputation.