New Delhi, Feb. 11 -- Comedian and filmmaker Varun Grover says he has retired from ranting. But, he says, Mumbai's metro system pulled him back in.

In a viral video, Grover delivers a deadpan yet dramatic monologue about navigating the Mumbai Metro, calling it "the strangest metro line in the world".

"I know rants have become very outdated and I haven't been doing it for a long time," he begins. "But now I am not going to stop. This is the final tipping point."

His main punchline? The metro lines, he says, behave like strangers forced into the same city. "There are three lines. All three have different tickets. To go from Versova to BKC, first you have to get on one line and then get off. Then you have to take a separate ticket for the...