Ted wonders if he should explore other career options; Marshall tries to lure Ted to the roof for a surprise birthday party.
A stampede at a comic book convention leads to an influx of colorful characters in the ER; Mark continues to make life difficult for Jackson; Ben returns and realizes Bailey has moved on.
An accident causes Ted to re-evaluate his life and his relationship with Stella.
Carrie makes Doug join a support group for overeaters, but he secretly joins an abusive relationship group where he blames his eating on her.
Jonah offers to help when Cloud 9 is flooded with people who want the flu shot, leading to his most stressful day yet; Amy and Carmen are asked to put on sombreros and hand out salsa samples.