This is arguably the most famous Season 2, marking first full year as the Tenth Doctor . It is defined by his romantic and protective relationship with companion Rose Tyler (Billie Piper).

The "Torchwood" arc, which leads to the creation of the spin-off series Torchwood . Key Episodes:

The emotional finale where the Daleks and Cybermen go to war, leading to the heartbreaking permanent separation of the Doctor and Rose.

Generally beloved for its high emotional stakes and Tennant's breakout performance. 2. The Fifteenth Doctor (2025)

Features the return of classic companion Sarah Jane Smith and K9 .