Doug Martin, the bartender at MacLaren's, is a brutishly large, toupee wearing man. He is also slightly dimwitted and angry but who is fiercely loyal to his regulars. That fierce loyalty leads to Doug challenging a group of bar patrons to a back alley fight on Lily, Robin, Ted, Marshall and Barney's behalf, but with the implication that Ted, Barney and Marshall join him in the brawl. After thinking about it, Ted, who has never been in a bona fide fist fight, believes a fight is something he needs to do once in his life and agrees to join Doug. Barney also goes to fight once he finds out that Robin, the hockey fan, is into brawlers. Marshall, on the other hand, won't fight, stating that he's been in many a fight before with his brothers and doesn't need to prove anything. When Ted and Barney come back from the fight with black eyes but are still standing while their opponents are out cold, they are seen as heroes by the other bar patrons, except for Marshall. Ted and Barney, basking in their new glory and with Doug vowing to provide them free drinks for life, have to make a confession about the fight when it has an unexpected consequence. Marshall also makes an unintended confession of his own about the history of his fights with his brothers.
The guys get invited to fight alongside Doug the Bartender. However, the fight doesn't go exactly how they imagined it to.
- Old Ted started the night by telling a story about the one fight he'd had in his life. Ted was getting pity from the waitress at the bar because he was "the guy who got left at the altar." Barney had gotten distracted by a woman he saw across the bar and began responding to anything he was asked by using titles of black sitcoms from the '70s and '80s. "Good times," Barney said.
Lily asked Barney if he wanted to go upstairs and do things to her that she wouldn't even let Marshall do. "Diff'rent Strokes," Barney said.
Doug, a bartender at McClaren's who's always "around," came around. He had a tendency to get violent and was especially sensitive about his hair. He was also very loyal to his regulars and wanted to make sure the gang always got to sit in their regular booth. He once kicked a priest and a nun out of the booth so Ted and Co. could have a seat. Doug was upset this time because the friends were sitting at a different booth when he went to kick three guys out of the regular booth. He came back, asked Robin and Lily to take a seat a their favorite booth and asked the guys for their assistance outside. They were going to fight the guys he'd kicked out of their booth.
"What's happening, now?" Barney asked.
The guys wondered whether they should go outside and fight. They debated the merits of fighting. Robin talked about how she thought fighting was kind of totally hot. Marshall talked about how he'd been in fights with his brothers. Ted decided the fight was an experience he needed to have. Robin looked impressed, which Barney noticed before getting up and declaring he was going to join the fight.
Ted and Barney went outside to find that Doug had already beat up all three guys by himself. But Doug thought they'd helped him in the fight and told them they were going to get free drinks for life. Barney decided to make the story believable by punching himself in the eye and punching Ted in the nose. They walked back into the bar and Doug had already told everyone inside the story. The crowd cheered as Doug called Barney and Ted "the guys who had my back!"
Robin was turned on by Barney's swollen eye. Doug brought drinks to the table and gave everyone but Marshall a free drink. Marshall had to pay $7.50 because he didn't have Doug's back. The gang made fun of Marshall for wussing out on the fight, and Lily later told Marshall he was right not to fight. She asked him to talk to her Kindergarten class about choosing the path of nonviolence.
The next day the kids called Marshall a wuss. Back at the bar, Ted and Barney were telling some girls about their fight. They looked over and saw two guys sitting in their booth and they went over to kick the guys out of the booth. The guys were actually there to serve Ted and Barney with papers informing them they were being sued for assault.
Marshall messed with the guys and told them they could be looking at some serious prison time, even though he knew they would probably only be facing a small civil settlement. They finally admitted they weren't actually involved in the fight. Marshall was satisfied. Robin came over to ask Barney on a date, but Marshall told her they faked the whole thing and Robin was suddenly uninterested in Barney.
Back at the bar, Marshall told the guys he got the other dudes to drop the lawsuit, but that meant they'd thrown angry, irrational Doug under the bus. He found out and took Barney and Ted outside, where Marshall, Lily and Robin all watched along. Doug was ready to beat up Ted and Barney when Barney ran away screaming. Marshall explained to Doug that Ted wasn't involved in the fight and Doug agreed the story made sense. Still, he was upset the guys didn't have his back. He told Ted he couldn't be counted and added, "No wonder your fiancée left you."
That did it. Ted, enraged, took a swing and punched Doug square in the face, hurting his hand. Doug shook off the punch and gave Ted one in return, which knocked him to the asphalt. Ted didn't remember much about the rest of the story, but when he came to, he saw Doug knocked out on the ground with Marshall holding Doug's toupee. It turned out Marshall's fights with his brothers were about more than playful roughhousing.
Ted went to Lily's school the next day to share his story, and the kids called him a wuss.