When Duty Calls - Season 1

Jun Guang and Long Bin are colleagues in the army. Jun Guang and his sister, Mei Guang, manage a bakery which supplies bread to the cafe that Long Bin is working at. Long Bin hopes for a promotion but the boss decides to give the position to his son, Jin Bao. Jing Yu likes Jun Guang but Jun Guang is in love with Yi Xuan. Yi Xuan's boyfriend passed away but she can't seem to move on.

After moving from Australia, Long Bin's wife, Yi Xin, cannot adapt to the life in Singapore. Her brother, Wei Guo, is forced to return home to fulfil his national service but he feels reluctant. Yi Xuan's sister, Yi Yun, is an aircraft maintenance technician who falls in love with Wei Guo at first sight. Jin Bao discusses with Jun Guang about the pricing of the bread and get along really well.

Yi Yun and Wei Guo's relationship develops quickly and become a couple. Mei Guang's son, Xian Feng, has a crush on Yi Yun. He is heartbroken after finding out that she has a boyfriend. During Xian Feng's low time, he meets Yong Zheng and the two hit off really well. Mei Guang sees Yong Zheng's figure by chance and quickly hides in shock.

Xian Feng and Wei Guo enlist into the army and become buddies. Wei Guo treats Xian Feng as an eye sore. Xian Feng does not know that Yi Yun is Wei Guo's girlfriend. Mei Guang tries to match make Jing Yu and Jun Guang. Jun Guang asks Yi Xuan to act as his girlfriend so as to make Jing Yu give up. Jun Guang suddenly confesses his love to Yi Xuan, which cause her to be at a lost.

After being kissed by Jun Guang, Yi Xuan does not contact him again. Jun Guang, Long Bin and Jing Yu are sent overseas for a military training. Before he sets off, Jun Guang still did not get any reply from Yi Xuan. He regrets kissing her. After the training is over, as they are about to return to Singapore, they encounter an earthquake. Jing Yu injures herself while saving Jun Guang.

Jun Guang, Long Bin and Jing Yu encounter an earthquake overseas after their military training and volunteer to stay back to help. Jun Guang is swept away by strong current in the river while trying to save a boy stranded on a tree trunk. Yi Xuan and Mei Guang rushes to Yusloka after receiving the news. Fortunately, Jun Guang returns safely before Yi Xuan and hugs her tightly. Yi Xuan finally accepts his love.

Yi Xuan's subordinate, Nick, is being held captive by a loanshark named K-ge at a pub. Yi Xuan arrives at the pub to save Nick. She encounters Hong Xun, who has similar catchphrases as Ming Yao. Jin Bao begins his In-Camp Training (ICT) and finds out that Long Bin is actually the Officer in Command (OC). Long Bin does not regard Jin Bao as his superior and treats him strictly.

Jin Bao feels that Long Bin is deliberately against him. Yi Xin pretends to be sick to make Long Bin stay with her instead of going back to camp. Long Bin finds out the truth and quarrels with Yi Xin. However, Yi Xin ends up really sick and is hospitalized. Feeling guilty, Long Bin apologizes to Yi Xin and they patch up. Mei Guang bumps into her ex-lover, Yong Zheng.

Jin Bao volunteers at a nursing home and sees Mei Guang coincidentally. Mei Guang is there to visit her father, Jia Ding, but takes care of the other old folks as well. Jin Bao feels that Mei Guang is an angel and is deeply attracted to her. He is delighted after discovering that Mei Guang is the "little white boat" that he admired when he was young.

Jin Bao realizes that he blamed Long Bin unjustly and reconciled with him. The duo work together to solve the cafe's crisis. Xian Feng and Wei Guo are punished to be on weekend duty. The two discover a recruit who is trying to escape while they on night patrol. Their friendship takes a better turn after working together to catch the recruit. Xian Feng advises Wei Guo to stop isolating himself. Wei Guo finally makes a change.

Thinking Jinbao and Longbin are not on good terms, Junguang invites them out for a drink and tries to mediate. He is unaware they have already cleared up their misunderstanding. The three men bump into Xiaochen, the culprit behind the food poisoning case. Xiaochen rallies his gang to attack them, to take revenge for his arrest. Jinbao, Longbin and Junguang are outnumbered, but are able to pull off a coordinated and flawless escape. The incident establishes a bond between them and they become firm buddies. Yixuan cooks a meal for Junguang. She comes across Mingyao's watch and starts thinking about him. Yixuan's mother has a dispute with a beauty salon, and her request for a refund is rejected. Junguang recommends consulting Yixin, who's a lawyer. To Yixuan's surprise, the lawyer who attends to her and her mother is Hongxun. Yixin has been called to an urgent meeting and is unable to meet them. Yixuan buys Hongxun lunch, to thank him for giving them a free consultation. He tries to ask her out again, but his mannerisms remind her of Mingyao and, excusing herself, she leaves in a hurry. Jinbao tries to avoid Summer. He hides in the store room and accidentally locks himself and Meiguang in. He becomes infatuated with her, and goes all out to court her.

Meiguang is frustrated by Jinbao's attentiveness. To show his sincerity, he declares he will score a gold for his IPPT to win her acceptance. Junguang assures Meiguang it's impossible for Jinbao to obtain a gold. Kopi Kia's business slumps after the food poisoning incident. Longbin decides to launch a new flavour of toasted bread to attract customers. He is enthused about avocado toast he had tasted at a small coffee stall and tries to recreate it to suit Kopi Kia's menu. The customers' response is favourable. However, some netizens allege that the toast is not original. Yixin finds out she is expecting. She and Longbin are overjoyed. To their dismay, Yixin's mother returns from Australia at the news. Her strict control of Yixin's diet and habits puts stress on Yixin. Following their outstanding performance in Basic Military Training, Weiguo and Xianfeng are chosen for Officer Cadet School. Meiguang worries about how the rigour will affect Xianfeng. Xianfeng tells Junguang he intends to sign on with the army, and asks him to keep it a secret. Yongzheng takes Xianfeng home. He is stunned to learn Xianfeng is Meiguang's son, and suspects Xianfeng is his son. Yiyun joins Xianfeng and Yongzheng when they meet to play drones. Yongzheng grabs the opportunity to collect samples of Xianfeng's perspiration for a DNA test.

Hongxun sees Yixuan often, due to her mother's case. They discover they have a lot in common and get along well. He shows he likes her, and she can't resist him as he reminds her of Mingyao. Business at Kopi Kia picks up as its 30th anniversary approaches. Recalling the past, Weirong thinks about his old friend A-shui, and regrets not being able to apologise personally for his misdeeds. To fulfil his father's wishes, Jinbao goes to the nursing home to look for information on A-shui. Meiguang realises Jinbao is actually a filial son. Her perception of him changes. Junguang is sad that Yixuan and Hongxun seem very close. In fact, Yixuan has rejected Hongxun's declaration of love, saying she already has a boyfriend. Hongxun does not intend to give up pursuing her. The DNA test shows Xianfeng is Yongzheng's son. Yongzheng is astounded. He buys a drone for Xianfeng, saying he and his wife have no children and he is treating him like his son. Meiguang is startled to see Yongzheng and Xianfeng together. She worries that Yongzheng will tell Xianfeng his true paternity.