ChRiStInA ApPlEgAtE ReTuRnS To SaMaNtHa WhO? SeT

Christina Applegate has returned to work, her rep confirms to PEOPLE, as filming on her ABC comedy Samantha Who? resumed Monday in Los Angeles.

The actress underwent a double mastectomy in July, after being diagnosed with breast cancer. The surgery was a success, and Applegate, 36, says she's cancer free.

Applegate subsequently appeared on the Sept. 5 Stand Up to Cancer telethon, and is expected to present at the Primetime Emmy Awards on Sept. 21. She is also nominated as lead actress in a comedy series.

Samantha Who?'s second season premieres on Oct. 13.