Rob Lowe Scrubs in For His First Day on 'Code Black' - See the 'Medical Boot Camp' Pics!

Rob Lowe has officially checked in to Angels Memorial Hospital!

Just one day after it was announced that 52-year-old actor will star in Code Black's second season, Lowe has already scrubbed in on set.

The West Wing alum took to Instagram to document his doctoral debut on the CBS medical drama with an all-smiles pic besides his new co-stars Marcia Gay Harden and Luis Guzman. "First day of medical boot camp on #CodeBlack. #Selfie surrounded by great actors," he captioned the photo.

MORE: Get the Details on Rob Lowe's Aggressive 'Code Black' Character!

Lowe, who most recently starred in the short-lived Fox comedy, The Grinder, is taking on the series regular role of Col. Ethan Willis, a U.S. military doctor described to have an "aggressive and rule-breaking" medical style.

Star Benjamin Hollingsworth, who plays Dr. Mario Savetti, dished on Instagram that the cast is "beyond excited" to welcome Lowe to the "#CodeBlack family," and Harden snapped a sweet pic of the first table read of season two.

Although Wednesday was Lowe's first time at the operating table, the rest of the Code Black cast are now experts at on-screen surgeries. Last September, ET was on set during the series' medical boot camp to watch the actors get a crash course in trauma technology, terminology and performing real-life procedures.

EXCLUSIVE: Behind-the-Scenes With the 'Code Black' Stars in Medical Boot Camp!

"The terms are really hard you can't really do a good job if you don't know what you're talking about," Harden previously dished. "There are a lot of terms and they come fast and furious because the show is docu-style, so we're here at boot camp and we're actually learning to do what we need to do."

Fingers crossed Lowe will be able to pick up on the hospital lingo and techniques quickly since he's set to appear in Code Black's season two premiere on Wednesday, Sept. 28 on CBS.