set the fire on fire 

said to a person who is doing more harm than good but because you're already in such a horrifying situation, which you think couldn't get worse, that it doesn't matter as this person's efforts are pointless and wouldn't make any difference.

A: I can't believe that you two broke up.

B: he learned what have I been doing... Jes is going to tell him that I cheated on him with john. She's just setting the fire on fire I've told so many lies , another one won't hurt

(imagine two criminals that are stuck in a room and if they can't manage to get out they'll die. there's only a desk and an old phone in this room and the police is already after them)
A: what are doing?!
B:I'm calling the police
A:what?! whatever, set the fire on fire we're going to die anyway/ we're gonna get arrested anyway

set the fire on fire by ohnoohnoohnonononono January 21, 2021

Set the city on fire 

Mass Appeal
A term used in rap music and modern slang meaning to excite and interest a large amount of people.

"You heard that new Jeezy track? He's finna set the city on fire with that shit my nigga!"

"That law donne set the city on fire... now a nigga can't get strapped!"

Set the city on fire by KING990 June 28, 2009

they didn't set the world on fire

A phrase used to describe the averageness of a group of people's actions or behaviours.

Also meaning, nothing special, just average, not 'hot' or on fire.

'They' can be replaced by another pronoun if used to describe a singular person/place/event:
e.g. he/she/it didn't set the world on fire

John: Did you like the concert? Were the Rolling Pebbles any good?
Tim: Oh well look, they didn't set the world on fire but they were alright.

they didn't set the world on fire by Briollette August 31, 2006