Jerod Harris- Getty

Will Ferrell sporting a Ron Burgundy mustache, and Shawn Johnson among other celebrities’, participated in the Halloween themed Rock ’n’ Roll Los Angeles Half Marathon benefiting the ASPCA.

Will and Shawn joined over 12,000 runners who rocked the streets of downtown Los Angeles in costume alongside other celebrities including Andrea Barber, Neil Everett, Brandon and Leah Jenner.

Key highlights-

Will Ferrell– as Ron Burgundy- finished the half marathon in 2:03:49

Olympian and DWTS Shawn Johnson took a break from dancing (and preparing for this week’s country theme) to run the mini- marathon.

After finishing the race, Shawn checked out the adoptable dogs hoping to find her a furry friend.

American Idol’s Skylar Laine pumped up the crowd with the National Anthem after meeting her “idol” Shawn Johnson

Andrew McClanahan- PhotoRun.net

Andrea Barber– everyone’s favorite and Full House’s Kimmy Gibbler- ran the ENTIRE race as a “run-away” bride. She was a top 10 finisher in the costume contest.  She told fellow runner’s about how much she loved the Full House reunion and how they are all going to get together more often.

Finish Line concert by The Dirty Heads with opening act Camryn