In America, in 1987, three young Holby familiars make a pact to push the boundaries of medicine no matter the cost. With the life of a friend hanging in the balance, Gaskell must question his unshakeable belief in Project Laszlo.

As Holby reels from tragic news, Sacha takes on a marathon operation. But Dom worries he's taking on too much too soon. Serena is pulled in all directions when Leah, a sparky new junior doctor, struggles with a problematic first patient. Fletch sets about stealthily engineering some quality time with Steven.