Barney has to decide between his trademark suits or a beautiful bartender (Stacy Keibler) in the 100th episode, which includes a musical number by the cast called "Nothing Suits Me Like a Suit." Cindy: Rachel Bilson. Tim: Tim Gunn.

James Belushi and Jerry O'Connell host a sneak peek at the five new series ("Hawaii Five-0," "Blue Bloods," "The Defenders," "Mike & Molly," "$#*! My Dad Says") on CBS' 2010 fall lineup.

While Alan and Jake are away on a road trip, Charlie is visited by the ghosts of his former girlfriends. ZZ Top make a cameo appearance.

The friends try to help Sheldon overcome his fear of speaking in public.

A homeless man is accused of murdering a prominent heiress, and former CSI Eric Delko (Adam Rodriguez) assists with his case by appearing as an expert witness at his trial, which pits Delko against his former lab partners.