Life on the Line.

Following the death of his wife in a hit-and-run accident, principal ambulanceman Mak Chay-tin lives with his only daughter Lok-yee, sister Oi-fa, and sister-in-law Cheung Ho-kei. The young and naive subordinate Cheuk Ka-kit is impulsive and clashes with Chay-tin's life, while Tam Ka-jun, the training director, pursues perfection and picks on Ka-kit, creating pressure on the team. Chay-tin, being the middleman, works hard and strives to maintain the unity and cooperative spirit between the team members. He also hopes to cultivate outstanding ambulance elites, rescuing more precious lives in challenging situations.