Elizabeth, Henry, and Isabelle will launch into the plane crash that killed Secretary of State Vincent March in "Madam Secretary" episode 9 tonight! Find out where to watch online a free live stream of "Madam Secretary," titled "So It Goes," via CBS live streaming.

If you can't make it to a TV by 8pm EST tonight to catch "Madam Secretary" episode 9, click here or here to watch "So It Goes" online via a free live stream.

If that doesn't work, CBS also offers episodes on their website to watch online the morning after an episode airs.

The synopsis for "Madam Secretary" episode 9 reads: "Elizabeth, Henry and Isabelle launch their own investigation into the plane crash that killed former Secretary of State Vincent Marsh. Also, Nadine takes a step back into the dating pool when she agrees to go on a date with a NASA scientist."

Will they find out who killed Vincent Marsh? Tune into the live stream tonight to find out!

According to Cartermatt.com, this time in the season of a new series is the "make-or-break" period, when the story needs to rise to another level to draw in a devoted viewership.

USA Today is not convinced "Madam Secretary" has what it takes to be a hit yet and is managing to stay afloat thanks to the performances of Tea Leoni and Tim Daly. "Broadway great Brian Stokes Mitchell stars as the late Vincent Marsh, as one of the season's more improbable hits doubles-down on its continuing story of the mysterious death of the late secretary of state," USA Today writes. "So much of 'Secretary' doesn't, or at least shouldn't, work - starting with this continuing conspiracy and moving on to Henry's secret spy mission and the show's desperate attempt to make a couple out of the chemistry-free Matt and Daisy. (No one is ever going to call them "Maisy," CBS. Just - stop.) And yet it remains one of the new season's more dependably entertaining hours, thanks in large part to very appealing performances by Tea Leoni and Tim Daly, who make their characters and their relationship feel credible, even when common sense tells us they're not."

Catch " Madam Secretary" episode 9 tonight at 8pm EST on CBS.