Trama

Barney tries to do all the items on Ted's "I'm too old for this stuff" list while Marshall's over-competitive side comes out when he coaches Lily's kindergarten basketball team.

After Barney is banned for life from the local laser tag club for his rough play, Ted adds it to what he calls his "Murtaugh" list, named after the Danny Glover character in Arma letale (1987), he who said "I'm too old for this $#*!". Barney ends up seeing Ted's Murtaugh list as a challenge and bets Ted that he can do everything on the list in twenty-four hours. Conversely, Ted tells Robin that he is looking forward to growing old. So Robin and Barney come up with an alternate list of "old folks" things for Ted to do, Ted who double bets Barney that he can complete the items on that list before Barney finishes the Murtaugh list. Meanwhile, after Lily asks him, Marshall agrees to coach Lily's kindergarten class' basketball team. Lily sees it as potential dad training for Marshall. But Lily may change her mind when she sees that Marshall is a dictatorial taskmaster as a coach, as opposed to the touchy-feely coach she wanted.—Huggo

The episode begins with Barney recalling the events of the previous night to the rest of the gang, in which he is accused of being too rough (Disorderly game play, 3 counts of shoving) during laser tag by the game's owner McCracken (Robert Wisdom). McCracken takes away Barney's ID and gun, but Barney begs that the game is his life and gets one last chance (the game is all he got and is close to having tickets for the remote controlled helicopter). 30 seconds later, Barney is caught again and this time banned for life. He then reveals plans to break into the laser tag arena and throw toilet paper everywhere. He is shown arguing with the owner in a parody of a scene often used in crime shows. Ted brushes it off, informing Barney that he is too old for laser tag. Ted then reveals "The Murtaugh List", a reference to the Roger Murtaugh character from the Lethal Weapon series, whose signature phrase is "I'm too old for this shit". Throughout the episode the narrator Ted replaces the word "shit" with "stuff" as he retells the story to his children. Ted's use of the list is to keep a record of the things he believes he has become too old to do anymore. Like Marshall's beer bong, which induced severe hangovers for Ted by the time he was 30 and made him realize he was too old for this shit.

Barney accepts Ted's revealing of the list as a challenge, and makes a bet with him that he can perform every item on the list within the following 24 hours. If he does, Ted will TP the laser tag place with him. If he cannot, he will spend three hours listening to Ted talk about architecture, an idea so horrible even the thought of it causes him to twitch involuntarily.

Meanwhile, Marshall has taken on the role of coaching Lily's kindergarten's basketball team. Lily saw it as dad practice. He is extremely aggressive in training the children, doing such things as forcing them to run and throwing basketballs at them when they don't conform to his standards. A flashback shows his father relentlessly training Marshall, yelling at him aggressively. Lily is shocked by this, as her usual training tactics involve playing a guitar and allowing the children to do whatever they like. She says that the games don't keep score and everyone gets a participation trophy.

Barney continues to try to perform every action on the Murtaugh List, contracting an ear infection and spinal injuries in the process, from self-ear-piercing and sleeping on a futon, respectively. During a conversation with Robin, Ted reveals that he would prefer being older to being younger. Upon hearing this, Robin and Barney make Ted his own list of things he would do when he was older (Put on reading glasses, yell at neighborhood kids, supper at 4 pm). Another bet is made between him and Barney to see who can complete their respective lists first, thus introducing the "gentleman's agreement". Barney has to listen to Ted for 6 hrs if he loses, and cannot do anything on the Murtaugh list ever again. If Ted loses, he has to buy the toilet paper as well.

Lily grows tired of Marshall's over competitive coaching and tells him off - fearing he will be father as he is a coach - forcing him to be less like his father and go easier on the children. Lily threatens to silently treat his ass into the ground, unless Marshall acts like a teddy bear full of cotton candy and rainbows. During the game, they lose without scoring a single point (118-0), but Marshall realizes the value in playing for fun and makes good with Lily. He gets a participation trophy as well.

Barney dyes his hair a funny color and then goes to a rave. After being drugged at a rave, Barney is finally forced to accept the reality that he is growing older and gives Ted the victory. Having re-watched the complete Lethal Weapon series, Ted realizes that Murtaugh still did the things he claimed he was too old for, and decides that he has more to live for than waiting to grow older. He agrees to accompany Barney in covering the laser tag arena with toilet paper, despite winning the bet. Ted, Robin, and Barney are discovered by the laser tag arena owner, who pretends to be accepting of the situation before going to call the police and he walks away.