When lawmakers left Washington in mid-July for their long summer recess, they still hadn’t finished the job of funding the government. Now, with the October 1 deadline looming, Congress is headed for another high-stakes showdown that could leave the U.S. teetering on the brink of a shutdown.

The last time they faced this cliff, back in March, Congress barely scraped together a stopgap deal to keep the lights on. That measure runs out at the end of September, and this time, the math is just as unforgiving. House Speaker Mike Johnson can lose only three Republican votes to pass a bill without help from Democrats, while Senate Republicans would need at least some Democrat support to clear the 60-vote filibuster threshold.

Senate Minority Leader Chuck Schumer shocked many in his own party last time when he helped break the filibuster to avert a shutdown under President Trump. While he didn’t vote for the bill itself, Schumer argued that avoiding a shutdown was better than letting Trump and then-DOGE head Elon Musk have the chance to keep parts of the government closed indefinitely. Progressives fumed over his move, seeing it as a missed opportunity to extract concessions from Republicans. The backlash was so intense that some Democrats even called for new Senate leadership.

This time, both Johnson and Schumer face an even more tangled web. White House Budget Director Russ Vought has said he wants a more partisan approach to spending bills, but numbers are numbers — neither chamber’s Republican leadership can get around the need for at least some Democrat buy-in if they hope to pass anything.

Adding to the tension, some members of the conservative Freedom Caucus are floating an unusual strategy: simply re-upping current funding levels. That would mean continuing budgets set under Biden and a Democrat-led Senate, but with one twist — it would freeze spending instead of allowing it to rise. In Washington terms, that’s a quiet but significant cut, and it’s an idea some fiscal hawks find appealing.

Still, that approach could spark resistance on both sides. Democrats would likely demand more funding in any renewal, while some Republicans are looking for deeper cuts to meet the demands of DOGE’s aggressive budget targets. Congress has so far only delivered $9 billion in reductions, mainly from public broadcasting and foreign aid — a drop in the bucket compared to what fiscal conservatives want.

For Schumer, the question is whether to drive a harder bargain than he did in March. Progressives will expect him to push for major concessions before agreeing to break a filibuster. For Johnson, the challenge is holding his fractious caucus together while keeping any deal in line with President Trump’s priorities.

If neither side can agree, the Capitol could descend into what one lawmaker has called a “chamber of horrors,” with other legislative business grinding to a halt while the two sides trade blows over spending. The closer the calendar gets to October 1, the more intense — and unpredictable — the fight will become.

In the end, both leaders will have to decide how far they’re willing to go to avoid a shutdown — and how much political candy they’re ready to give the other side to make a deal. For now, the mood on Capitol Hill is less “trick-or-treat” and more “watch your back.”

If history is any guide, the scariest part of this fiscal Halloween season may be what happens when the clock runs out and there’s still no deal on the table.