Heartbeats tells the story of a love triangle between two friends and a captivating stranger, exploring themes of friendship, jealousy, and unrequited love in the vibrant city of Montreal.

The series is set in the mid-1980s, at the end of the Cold War. Red Ketchup is assigned the most perilous missions by the FBI, and he pulls them off every time. The sight of his hulking frame, red eyes and orange hair is enough to make enemies quake. He breezily and brazenly takes every risk to achieve his ends, usually causing heavy collateral damage along the way. The FBI regards him as a liability and sends him to distant lands hoping he will never return. But Red Ketchup always makes it back!

Taking advantage of his mother's absence as she departs on a cruise ship for some rest and relaxation, 12-year-old Félix sets out to find his father, a fisherman who disappeared at sea two years earlier.