It's the first day of varsity, and Boon Keong meets Angel for the first time at the swimming pool – he's the lifeguard, and she's the pool attendant. We meet the rest of the characters for the first time as Prof. Diane pulls together a team of water polo players. Jess eyes Max at the water polo training, and sets her sights for him. However, Boon Keong is infatuated with Jess. Boon Keong also meets his father, Greg, for the first time. They are classmates, and to his horror, everyone finds out they are father and son. Boon Keong is reluctant to join the water polo team – will Prof. Diane and the others be able to convince him?

Boon Keong moves into the hostel for the first time. Prof. Diane coaches the first training and they play their first water polo match. Greg soon learns that he is too old to play, but gives Prof. Diane good advice on water polo tactics. She ignores Greg though, and it looks like the boys might lose this match…

The boys lose the match badly and Diane realizes that they might have won if she had listened to Greg’s advice. Meanwhile, Jess and Max begin their relationship much to Boon Keong’s jealousy. Will Prof. Diane overcome her pride and ask for Greg’s help or is the team destined to be beaten.

Prof. Diane and Greg coach the team together for the first time and could not agree on anything. Boon Keong contemplates leaving the team now that his father is on it. Both Greg and Book Keong almost come to blows in the pool. Boon Keong confesses to Angel about his feelings for Jess. Angel, on the other hand, secretly pines for Boon Keong. If the water polo team is to do well, they must learn to accept and compromise with each other – but can they do so before the next match?

Prof. Diane and Greg coach the boys together – and an exhibition match against a rival team goes well. Morale is up for the team. Max holds a pool party at his condominium to celebrate their improvement. The cracks in Max and Jess’ relationship begin to show. Jess starts to eye Boon Keong as her next target, and he reciprocates. Boon Keong and Max get into a drunken brawl because of Jess. Jason begins challenging Boon Keong for leadership. The boys play their second match. Will they win, or will their emotions prevent them from doing so?

The boys win their second match, mainly due to Greg’s advice. The boys are ecstatic, but Boon Keong is irritated that his father is interfering in a game that he feels that he could have won, alone. Jess and Boon Keong begin dating secretly behind Max’s back. Angel discovers this, but keeps it a secret for Boon Keong. Jason also discovers this, and threatens to walk out on the team. Meanwhile, they begin to learn of Tom’s drinking problem, and he begins coming late for trainings…

Tom’s tardiness and alcoholism becomes more evident – but as their star player, they need him. Russell backs him up even as Jason argues that he should be sacked. Jin (streetwise) and Alan (book smart) also argue about tactics and techniques for the next game. Boon Keong is unable to settle the disputes. The team has its first real crisis, and the team looks ready to fall apart. Max and Jess break up, and with Boon Keong in the picture, the unspoken tensions are carried over into pool violence.Friction heats up between Jason and Boon Keong, as Jason thinks he’s the better player, and therefore should be captain. Can the pair resolve their differences in time for the next match?

Jason challenges Boon Keong to a one-on-one match, and wins. He then wrests captaincy away from Boon Keong, and commands the team. Jess comforts Boon Keong, and they begin a relationship together – to Angel’s disappointment. The boys begin their third match. But with their loyalties divided between Jason and Boon Keong, how will they co-operate to win the game?

The boys lose their third match, mainly due to Tom’s drunkenness, Jason’s inept leadership, and their inability to co-operate. Boon Keong tries to confide in Jess, but she’s not as good a listener as Angel.

Jason relinquishes leadership to Boon Keong, having realised who is the better captain. But Boon Keong’s first action is to shut Greg up during trainings and matches. The boys play their semi-final match – but with one man down, can they still win?

The boys narrowly win their semi-finals – but morale is down. Prof. Diane and Greg decide to hold a training camp for the boys to regain their morale and train for the finals.

The boys prepare for the final match, but without Tom, they know they have no chance of winning. Prof. Diane finally realizes that team spirit is more important than personal glory, and reassures the boys that even if they lose, she will still be proud of them. She also reveals to them Tom’s past. The final match begins!

Polo Boys is a coming of age drama series about a motley crew of diverse young men (who would never have been friends under normal circumstances), brought together by Coach Diane Lee (a self-absorbed lecturer who herself has lessons to learn about life) to form a water polo team. These young men are challenged to overcome obstacles that they've never faced before, deal with grown-up complex issues like teacher-student relationships; and to strike a balance between school and peer and family. Being a member of the water polo team makes these boys realize the importance of friendship, learn to cast away differences, embrace teamwork and grow to manifest the spirit of true sportsmen.