Prologue:

The gang was sitting at their usual table at MacLaren's. Lily and Marshall sat on one side, and Ted and Robin sat on the other, with Barney sitting in a chair in between them. Suddenly, Barney's phone started ringing a strange tune. He had a brief look of panic in his eyes as he answered. Three men dressed as cowboys popped up from behind his chair, singing:

"Bad Horse

Bad Horse

Bad Horse

Bad Horse

He's gotten all the e-mails

That you've been sending him,

But he's put them directly

Into his trash bin.

He doesn't like excuses,

So just put up with all abuses.

Giddy up the pace,

Stay the course,

Or it's 'Goodbye, Wilbur.'

Signed, Bad Horse."

"What was that!" asked Marshall, excitedly.

"Nothing," said Barney, gulping loudly. "Nothing. Oh, what's that over there?" He pointed into the distance, and then he suddenly stood up and ran out, his limbs flailing about as he left the bar.

"Okay," said Ted. "That was really weird. Even for Barney."

"Yeah," said Marshall. "You can say that again."

"You know," said Ted. "I should really wear my red cowboy boots more often..."

"No!" all three chorused.