Ryotsu chasing idol stardom is the purest expression of what makes Kameari tick: absurd premise, zero self-awareness, total commitment. The show doesn't slow down to explain the joke or wink at you. It just builds a scenario where a middle-aged cop genuinely believes he has what it takes, and lets that conviction do all the work. You're not laughing at him. You're laughing because he's right about being completely wrong.
A new idol unit is put together with one purpose: spreading the message of traffic safety. The title points to Ryoutsu's own route toward idol fame, and the result is a comedy special from the Kochira Katsushikaku Kameari Kouenmae Hashutsujo franchise, made after the TV series ended. It first aired in two parts, though some streaming sites present it as a single episode running about 46 minutes.