We’re all gearing up for the Season 15 finale of CBS’s hit summer reality show Big Brother, and while we know that Spencer, GinaMarie, and Andy are the Final 3, we have no clue who will win! But one thing we know for sure: host Julie Chen promises that tonight’s finale will be “SO good.”

Check out this behind-the-scenes photo that Julie shared from Tuesday night’s rehearsal. “1 more day til the #BB15 finale! In rehearsal and tomorrow’s show is going to be SO good,” she captioned the photo. Keep in mind that the finale is actually tonight since Julie shared this photo late on Sept. 17.

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OK, time for spoilers. GinaMarie won the first part of the final HOH competition and Andy won the second part. That means that those two will face off in the final part tonight and the winner will then choose which of the other two houseguests he or she would like to bring to the Final 2. Then the jury comes in and votes and someone wins a cool $500K. Not too shabby, eh?

Who do you want to win Big Brother 15? GinaMarie? Andy? Spencer? Hit the comments and let us know!

The finale of Big Brother 15 airs tonight at 9:30 p.m. ET on CBS after the 8 p.m. premiere of Survivor: Blood vs. Water!

Carson Blackwelder is an Associate Editor at Wetpaint Entertainment. Follow him on Twitter and Google+!