Friday's episode of MacGyver is all about our favorite computer hacker, who's about to start World War III after hacking the NSA -- unless MacGyver (Lucas Till) and Jack (George Eads) can find her first.
"We recruited her, got her out of prison," Jack explains.
"I guess I should thank you for that, and for saving my life. But it seems that you've dragged Riley into a very dangerous line of work," Diane says. "Do you remember the first time I let you watch Riley for me? Do you remember what I said?"
Find out what Riley's mom said -- and just how fierce she can be -- in the video above.