Safecracker is a review game I created years ago after watching a movie. I got the idea to have multiple cases, like safes, in my classroom, each with a three-digit combination. Inside each case would be a paragraph that had each sentence numbered from 0-9. Students, in groups, would have to find the three sentences that contained errors related to the grammatical concept we were reviewing, like double negatives in this case. After our lesson that covered the grammatical concept, the review game was on! If they found the errors, they would be asked to try that combination to open the next safe, which contained another paragraph. After 4 cases had been "cracked" there were prizes in the last safe. The activity has been so successful with my students that I decided to create an online/PowerPoint version that students could use on their own. What you are about to preview, and acquire for free, is an online/computer-driven version of the safecracker game for Double Negatives. For your benefit, I have included the correct combinations for each safe here: Safe #1, 359. Safe #2, 258. Safe #3, 079. Safe #4, 017. Enjoy...and your students will too. I promise. And look for other versions of the online review game from me.