Just Add Surprise is the ninth episode of Season 3. It premiered on February 1st, 2019 on Amazon Video.
Hannah and Darbie throw Kelly a surprise early birthday party, interfering with her plans to trick them into cooking the spell to keep the cookbook forever. To end the party, Kelly cooks a spell to make it the worst party but she spells herself instead, turning it into a never-ending party. When Piper finds the morbium in the trailer, Kelly spells her to forget magic. At first Kelly thinks the spell will work but she then later realizes that she was the only one who hated her party. Everyone else was having the best time of their lives. On realizing that it was Kelly who spelled her own party, Darbie and Hannah begin to suspect that Kelly might be the Night Bandit who has been spelling them but Kelly throws them off her scent. However, after the party, their fears are confirmed after finding that spell Kelly wants them to cook is a mislabeled copy of the "Keep the Cookbook Casserole" spell. Back on the island, Mama P. finds a note she wrote to remind herself to eat the quiche in order to remember magic. She decides to come back to warn Hannah and Darbie about Kelly.
- Olivia Sanabia as Kelly Quinn
- Aubrey K. Miller as Hannah Parker Kent
- Abby Donnelly as Darbie O'Brien
- Judah Bellamy as Jake Williams
- Catia Ojeda as Terri Quinn
- Andrew Burlinson as Scott Quinn
- Ellen Karsten as Gina Silvers
- Amy Hill as Mama P
- Aiden Lovekamp as Buddy Quinn
- Laya DeLeon Hayes as Piper
- Tess Paras as Erin
- Jolie Hoang-Rappaport as Zoe
- Charlotte Mary Wen as Young Mama P
Worst Party Ever Whipped Cream