The AWOL comedian dropped in unannounced at two popular comedy clubs late Wednesday, saying he had just arrived in Los Angeles and felt like performing.
Chappelle served up some impromptu standup to stunned audiences at the Hollywood Improv and the Comedy Store.
"The place went ballistic. The kids were on their feet. We had a college night going on," said Reeta Piazza, the Improv's special events manager. He showed up about 11 p.m. and did a 15- to 20-minute set that focused on current events.
Chappelle then headed to the Comedy Store on the Sunset Strip, where he performed longer than an hour, said Dean Gelber, the West Hollywood club's general manager.
"It was definitely a good set. He was having fun," said Gelber, who would only say he talked about a variety of topics, including politics. "Some of it was new material. He was definitely ripping."
The comic briefly spoke about his hit sketch series "Chappelle's Show," but didn't indicate whether it would return for another season, Gelber said.
Chappelle, 31, took off last month to South Africa for a "spiritual retreat," leaving his fans — and even his agent and publicist — wondering where he went.
But Chappelle denied checking into a mental facility or having a drug problem in an interview with Time magazine.
Instead, he fled to stay with friends in Durban because he wasn't happy with the direction of the show, which trails only "South Park" as Comedy Central's most-watched program.
Calls to Chappelle's publicist and Comedy Central were not immediately returned Friday.
An unnamed Comedy Central representative told the Daily Variety trade paper that network officials would be sitting down with Chappelle to talk business "really, really soon."
Gelber said he was dumbfounded when two employees came to him late Wednesday and said, "Dave Chappelle just got off a plane from Africa. ... He's in the parking lot."
"He was in a good mood," Gelber said. "He hung out a little afterward and took pictures with fans. And then he disappeared into the night."