When you’ve got Pitbull booked all week and then due to a cancelled flight, he can’t show up, what do you do if you’re the host of the Tonight Show? Of course, you call Jon Glaser at the last minute to head over to NBC Studio 6-B. And that’s how Friday’s Tonight Show went down; with Jon Glaser arriving on set and being introduced while still wearing his coat, hat and backpack. Even though Jon did get the call on the day of the taping, the backpack was just for effect. As Jon Glaser said, “I ‘fake’ literally just got here.” Jimmy Fallon needed a guest and instead of Pitbull, the audience got the “Glas-bull”.

Jimmy Fallon quickly put together an interview, discussing Jon Glaser’s most recent projects. He’s just finished shooting the second season of “Neon Joe, Werewolf Hunter” for Adult Swim. Jon said he’s sure he’ll be back on the Tonight Show to announce when the new season will premiere. Fallon added that hopefully Pitbull will cancel again to make that happen. The interesting backstory on Jon Glaser’s show “Neon Joe” is that it is the love child of a previous Tonight Show appearance about 3 years ago when Jon showed up and as a gag, dressed in a neon hoodie and announced that that he had a new show coming out called, “Neon Joe, Werewolf Hunter“. The good folks at Adult Swim took him seriously and decided to send the premise which had no script, no cast and nothing more than a title to series.

You can watch all of this on the Tonight Show clip below via NBC.com, but you’re being warned that it does contain a SPOILER ALERT! Or does it? Jon Glaser who plays Laird Schlesinger on Lena Dunham’s HBO comedy “Girls“, gave away how the series will wrap up in its end season finale. His spoiler, which Jon said may or may not be fake, includes Laird’s fate and what’s next in his character’s life. Watch only if you can’t wait for the actual “Girls” series finale.

Finally, Jon Glaser was fully aware that a lot of Pitbull’s fans would be disappointed to see him in the rapper’s place. So, he did the next best thing, at least as far at the Tonight Show is concerned. He went out lip syncing Pitbull’s hit, “I Know You Want Me (Calle Ocho)“. Its Mr. 305 checkin’ out and the Glas-bull checkin’ in.

You can see Jon Glaser in the final season of “Girls“, Sundays at 10pm on HBO and on the truTV series, “Jon Glaser Loves Gear” where you can get full episodes at truTV.com. And look for season 2 of “Neon Joe, Werewolf Hunter” on Adult Swim when Jon Glaser is back on the Tonight Show to announce the premiere.

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