Dr. Gregory Butler

"You’re smart, but not smart enough on me. I can kill you in any timeline I want, and nothing will be able to stop me."

- Dr. Gregory Bulter

Dr. Gregory Butler is one of the tritagonists of Happy Death Day and the main antagonist in the sequel of Happy Death Day 2U and he is the one who is now killing Tree and her friends and has his wife as an accomplice.

He was portrayed by Charles Aitken

Happy Death Day
He is seen in his class after he finished and was about to leave, Tree then goes to visit him since they still have an affair behind his wife Stephanie's back, of course she did find out about that, but Lori also has feelings for him when she was upset that Tree had an affair with him and his wife also find out about it. During the timeloop Tree decides to end her relationship with him, but after this he does not appear for the rest of the movie.

Happy Death Day 2U
Unlike the first timeline he's not having an affair with Tree, but with Lori instead his wife did not find out about the affair first, since Tree was not having an affair with Gregory but only Lori is. Tree heard him and his wife arguing about this after she did find out about the affair.

But him and his wife then conspired togheter to expose the affair, he of course disguises himself as the Baby Face killer to kill Tree and all her friends who get in his way while his wife goes after Lori, he always appears when his victims are unaware of his presence, but in almost the end of the movie he revealed himself as Tree and her friends killer, as his wife shot Lori, he then attacks Tree again as his wife give him the gun to kill Tree, but he shot Stephanie instead as he tells her he wanted a divorce as his wife slowly died.

As he is about to kill Tree for good, Carter then distracts him so that Tree can escape and he chases her to the exam room of an MRI Machine. As he was about to kill her, Tree then grabs him and threw him against the machine and stabbed him to death with a Screwdriver.

Victims

 * Tree Gelbman - Multiple times
 * Carter Davis - Multiple Times
 * Ryan Phan - Multiple times
 * Stephanie Butler - Shot to death