Today marks the first day of filming for Season 5 of Glee, news that would typically mean nothing but smiles and shouts of joy from our corner of the world.

Sadly, though, this season’s start has a much different feel in the wake of star Cory Monteith’s (Finn) unexpected death from a drug overdose last month. And while they’re thrilled to be back at work, Glee’s cast and crew members definitely have Cory on their minds as they begin work today.

“Day one season five. Something very big missing but everyone is happy to be together and back to work,” tweeted executive producer Brad Falchuk alongside a photo of the famous McKinley choir room red chairs where Cory spent so much time as the school’s unexpectedly talented football hunk.

Credit: Brad Falchuk on Twitter

Iqbal Theba (Principal Figgins) also shared his thoughts on the gaping hole left by Cory’s passing. “Back on the set for the 5th yr. Not the same as the last 4. Staying focused will be hard as hell.@GLEEon FOX,” he wrote.

We can only imagine how difficult going back to a place Cory spent so much time must be. They’ve already shared some of their hard work in a memorial video made special for Cory.

Sources: Brad Falchuk on Twitter and Iqbal Theba on Twitter