I am still happy, as while I think Jerome should have been the real Joker, interesting way to have the real j man arrive, and the same actor gets to play him again now!
The scene with the gas was straight out of the Mickael/Jack Batman film, the band riffed 1966 theme, and the end how Joker was born right out of him having one bad day!
If Jeremiah can even outdo the craziness of jerome.... They need to have bats by end of season!
Nota Bene : Jeremiah Arkham was revealed as a Joker wannabe in a recent comic book. It is probably a source of inspiration. You'll notice that Jeremiah Valeska has the same haircut than Jeremiah Arkham.