The tone of the election campaign has changed significantly in the past week, and it's virtually guaranteed that tonight's debate will reflect that.
The four leaders will most likely be dealing with ethics issues, as accusations of all kinds have been flying back and forth between them.
CJAD's political analyst Jean Lapierre says this is Quebec's dirtiest election yet.
"I've never seen something like that before," Lapierre told CJAD's Andrew Carter this morning. "I think this is the worst campaign on that front."
This has been a week full of allegations and insinuations — Couillard's account on the Island of Jersey, $400,000 possibly missing from the Liberals' books, a possible UPAC investigation into the Parti Québécois, and premier Pauline Marois refusing to reveal her tax information.
The PQ, meanwhile, has released a new series of radio attack ads, asserting the Liberals will control the Charbonneau Commission
Lapierre says the pressure will be on Marois tonight.
"She's got to show quite a performance because she's behind," he says. "Obviously, the trend will continue if she doesn't pull a big coup tonight."
And he adds Couillard's recipe for success tonight is to take the punches, and look like a premier.
CJAD will have special coverage of the debate this evening with reports every 15 minutes, beginning at 8 p.m., live blogging on CJAD's election page, and live-tweeting throughout the evening.