'Charmed' reunion puts fans through emotional rollercoaster on 'Grey's Anatomy'

ABC's "Cast From the Past" week-long event featured a very special Charmed reunion on Grey's Anatomy Thursday, as Holly Marie Combs and Alyssa Milano reunited with former Charmed producers and writers Krista Vernoff and Andy Reaser, who are now executive producers and writers on Grey's Anatomy.

Combs and Milano starred as the Peterson sisters, whose third sister suffered brain damage after falling at a construction site. Unfortunately, it wasn't quite the power of three since the third sister was not portrayed by Shannen Doherty. Doherty did, however, make a cameo on Riverdale Wednesday in honor of Luke Perry.

Following a lot of sisterly bickering, the two Peterson ladies decided to pull the plug on their sister, which had Charmed fans feeling déjà vu:

However, a major plot twist quickly turned the sad moment into a super hilarious moment, when Combs's character answered a phone call on her sister Heather's phone only to discover that it was Heather herself. As it turned out, Heather's bag was stolen, so the woman they had just unplugged was likely the thief.

Combs and Milano's reaction to the revelation had fans loving the Charmed-ness of the moment.

In the end, the sisters were relieved to discover they still had a third sister, which was also so very Charmed.

Grey’s Anatomy airs Thursdays at 8 p.m. on ABC.

Check out Shannen Doherty joining ‘Riverdale’ for a touching tribute to Luke Perry:

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