I remember watching a sci-fi movie in the early 00s. It was full of comedy. Here are the details I recalled:
There was a space opera TV show in the movie. It seemed a true copy of Star Trek (they used to pilot a ship and there were captain, first officer, science officer etc on the bridge). The name of the TV show was possibly the name of the movie.
Once the main crew of the TV show were celebrating some achievement, they were approached by humans having weird behaviour (they were aliens in disguise; in reality, they looked like an octopus).
The alien race was innocent. They couldn't comprehend the concept of art, lies etc. So, they believed that the TV show (they got the EM waves) was a true historical documentary of mankind. So, they came looking for help from the brave captain of the show.
From the TV show details, they had built a starship which worked. The aliens needed the TV show crew to pilot the ship to defeat another alien race that terrorized them. The TV show crew didn't have any problems piloting the ship as the controls were familiar, only these controls were real.
Parodying television series such as Star Trek and its fandom, the film stars Tim Allen, Sigourney Weaver, Alan Rickman, Tony Shalhoub, Sam Rockwell, and Daryl Mitchell as the cast of a defunct television series called Galaxy Quest, in which the crew of a spaceship embarked on intergalactic adventures. Enrico Colantoni stars as the leader of an alien race who ask the actors for help, believing the show's adventures were real.
Sounds like 'Galaxy Quest', featuring Tim Allen, Sigourney Weaver et.al. I use this 'The Historical Documents' myself. How would an Alien Species be able to tell fiction from truth? Very interesting points...