From ABC's website:

Tuesday, Mar. 8 at 9/8c
"The Mustache"
A hot delivery girl gives Jim some fashion advice, prompting him to grow a mustache, which Cheryl hates. Cheryl retaliates by becoming a brunette - but Jim loves it. After a chance meeting with the girl, Cheryl asks her to give Jim suggestions that will make him look ridiculous.


Not a good sign.