- Josh Radnor (Ted Mosby)
- Neil Patrick Harris (Barney Stinson)
- Jason Segel (Marshall Eriksen)
- Alyson Hannigan (Lily Aldrin)
- Cobie Smulders (Robin Scherbatsky)
- Cristin Milioti (Tracy McConnell)
How I Met Your Mother — S4E8
Episode: Woooo!
Air Date: 2008-11-17
Runtime: 23 min
Overview
A birthday party for one of Lily's co-workers leads to Robin connecting with a group of single partiers known as the "Woo Girls". Ted presents a plan for Goliath National Bank's new HQ.