Lea Michele and Cory Monteith

Lea Michele and Cory Monteith

Lea Michele is working with 'Glee' producers on Cory Monteith's tribute episode.

The 31-year-old actor died from an accidental heroin and alcohol overdose on July 13 and his grieving girlfriend and co-star wants to make sure the upcoming episode dedicated to him is perfect.

A source told HollywoodLife.com: "The producers are still going back and forth on what they want to do and clearing music for his tribute.

"The meetings are lengthy and Lea is a part of them to make sure everything is just right.

"It's still touch and go for all involved. Tears can and will happen.

"When they start filming the episode, everyone is going to be a mess. After they film that episode they are going to go on a break to recharge."

Cory battled drug addiction throughout his teens and first entered rehab at the age of 19. After suffering a relapse earlier this year, he checked into a treatment facility but overdosed after a night out in Vancouver with friends last month.

Cory's character Finn Hudson will be killed off the show in the third episode of the upcoming fifth season, which will deal with drug addiction.