It only took four months for Jon Stewart to return to The Daily Show, as the former host appeared on Monday's episode as the series' Senior Jon Stewart Correspondent.

But he wasn't there to take back the show, as new host Trevor Noah joked after Stewart appeared behind his desk in a T-shirt, like some Ghost of Daily Show Past.

Instead, Stewart and his "I'm not on TV anymore" beard made a passionate appeal to Congress to pass the Zadroga Reauthorization Act, which would renew the original act passed in 2010 to guarantee lifetime health care for 9/11 first responders. It was only funded for five years, Stewart explained, "so people wouldn't have time to cheat it, and so that you could scientifically prove a link between the responders' horrible diseases and the toxic air they were breathing, day in and day out, at Ground Zero."

Stewart and Noah went back and forth on why the bill, which expired in September, hasn't been renewed. As Stewart made his plea to the camera, Noah stepped into the role of a confused outsider. Every time Noah gave Congress the benefit of the doubt, Stewart would hit him back with, "You're not from around here, are you?"

"The only conclusion that I can draw," Stewart said, "is that the people of Congress are not as good as people who are the first responders."

To prove it, Stewart traveled to Washington, DC, with some of the affected first responders to try to get some face time with members of Congress who'd tweeted support for first responders but who nonetheless had yet to officially announce their support for renewing the bill. The only one who listened to Stewart's case in person was Ohio's Rob Portman, and he went on to sign later that night.

With nothing to lose (and with Noah taking a back seat), Stewart kept hammering Congress — especially Majority Leader Mitch McConnell. "He doesn't give a shit about anything but politics," Stewart said. He ended the show by asking the Daily Show audience to tweet at Speaker Paul Ryan and McConnell directly with #WorstResponders (though his first draft of a hashtag was "end the fuckery," which definitely has a ring to it).

This is far from the first time Stewart has advocated for the Zadroga Reauthorization Act. In fact, he conducted a powerful interview with four first responders on The Daily Show in 2010 — but only one, Kenny Specht, was healthy enough to return to the show on Monday. Two were too sick, and the other has since passed away. "[The first responders] have paid for this bill over and over again, with the lives of their friends and their health," Stewart said, heavy with frustration.

It was a powerful episode, largely void of The Daily Show's absurdist takes and cartoonish outrage. And for all the audience's obvious excitement over seeing Stewart return, the night's most startling, affecting image was him sitting at a table with Specht, next to three empty chairs.