Mark Bloom

When Ron hexes the day to prove superstitions aren't real, things at the hospital start getting weird. Joyce and Matt discover an employee's secret.

While a meningitis scare overwhelms the resources and staff of Princeton-Plainsboro Teaching Hospital, House zeros in on a single patient: a 12-year-old whose symptoms are similar to, but not quite right for, meningitis. Cuddy gives them an hour to crack the case before pulling their medical manpower to treat the countless patients taking over the waiting rooms, but when they discover something quite unexpected, House, Foreman and Chase must devise ingenious ways and locations to treat the girl’s delicate condition amid the chaos. Meanwhile, House asks Cameron to come back to her job now that Vogler is gone, but she’s got a surprising requirement.

Season Three Finale. With Pied Piper's future in question, Erlich's publicity success leaves Richard in a moral quandary just as Dinesh's video-chat app starts to pick up speed. While Laurie prepares to jump ship, Gavin's comeback at Hooli is threatened by his displays of grandeur.

Bonnie and Adam’s romantic dinner is interrupted as the other ladies struggle with love on Valentine’s Day. Also, Wendy’s new relationship becomes the talk of the group.

Nick (David Giuntoli) and Hank (Russell Hornsby) are called to the scene of a crime where the suspect swears she was driven to madness by a very persistent talking wolf. Meanwhile, Nick and Juliette (Bitsie Tulloch) wonder if getting his Grimm powers back is worth giving up a normal life.Elsewhere, Bud (guest star Danny Bruno) hopes Trubel (guest star Jacqueline Toboni) can help take care of a wesen-related issue and the threats against Monroe (Silas Weir Mitchell) and Rosalee’s (Bree Turner) inter-wesen marriage heat up. In Austria, Adalind (Claire Coffee) continues her perilous trek in the hopes of retrieving her daughter.