In the episode “Time Bomb”, Lucas’ character Tabitha is being held hostage by Edward Nygma. Her hand is placed in a guillotine of sorts, and she is tasked with pressing a button that will let her go free but kill the other hostage or allow her hand to be chopped off and they both can walk free. Tabitha ultimately chooses to remove her own hand to give the other hostage a chance to live, and her hand is cut clean off. Upon pulling up her arm and glancing at her amputated hand, she passes right out (probably due to the pain or shock or both). The other hostage pleads to be let go to take Tabitha to the hospital, but Nygma is too dumbfounded to do anything. All he can do is watch Tabby’s eyes roll into the back of her pretty little head and slump down in her chair. He definitely did not see that coming.
This scene happens about 32 minutes the episode