How did it happen in the movie?
This scene opens with the arrival of Faramir’s company and their captives, Frodo, Sam, and Gollum, to a ridge, overlooking the city of Osgiliath. Looking down, they can see sings of the battle raging within, the city is afire. At this point, Frodo desperately begs Faramir to release them, claiming that the Ring would only bring destruction to Gondor. However, it is to no avail, Faramir simply orders his men to hurry on into the city, despite Frodo’s cries.

How did it happen in the book?
Actually, this scene doesn’t take place in the book. Faramir has already parted company with Frodo and Sam, letting them continue on their way. Afterwards, Faramir traveled down to the isle of Cair Andros, before taking three of his men and riding in haste for Minas Tirith. Before departing, he sent the rest of his company to strengthen Osgiliath.