In modern London, an adult man has dinner with his father at a restaurant. After their meal, his father sucks his thumb contentedly with no embarrassment or acknowledgment of the act. The son doesn’t make a comment, although he is surprised. When they walk back to the subway, the son says that the restaurant was fancy and inappropriate to suck his thumb in. The father says that “a man needs a hobby.” Three months pass, and the man calls his father one week before his birthday to invite him for dinner again. The father gives an unspecified alternative of what he’d rather do. The son asks if he can just come to watch. The father agrees and says that while his son doesn't have to approve, he wants his son to understand him for who he really is.   The next day, the two head to a private residence of a J.C. Tuck. They bring a bowl of guacamole. Tuck welcomes them into his home enthusiastically and has on a pair of tight black gloves. Various older men are sitting on floor cushions. Tuck places the guacamole on a table with other condiments, as well as potpourri, roses, perfumes, and a urine-looking liquid. Tuck commences the activity; the men begin to suck their thumbs and dip them into the condiments, eating and feeding each other vigorously. There are loud burp, fart, and slurping noises throughout the thumb-sucking session.   J.C. Tuck stands watching the men in satisfaction but does not partake in the activity. The son watches in horror. He steps outside to get fresh air, and Tuck follows him out to invite him to come back, arguing that it would not be cheating on his wife, simply tasting food. Tuck says that the thumb is the greatest gift God gave humans and that babies suck on them because they know they are sacred and want to keep it safe. The son becomes emotional, and Tuck encourages him to suck his thumb. He feels strange when he begins to do it, so Tuck sucks the son's thumb to show him, giving him great comfort. Then, Tuck removes his glove and reveals a stump of a hand with traces of blood and teeth marks. He says he likes to chew now, bringing it up to the son's mouth as the father comes outside and tells Tuck to let him go. The son and his father go home. 

When the son arrives home to his wife watching TV, he realizes how passionless their marriage has become. He kisses her hand, then begins to suck on her thumb in satisfaction and pleasure, but she seems unfazed. Then they decide to go to bed.