The Doctor's TARDIS (The Continuity Cap)
From Tardis Wiki, the free Doctor Who reference
In an alternate reality, The Doctor's TARDIS was disguised as a red Telephone box instead of a blue Police box. Due to the use of Continuity Cap, this TARDIS was swapped with the TARDIS of the prime Tenth Doctor.
When the Doctor undid the effects of the cCap, the TARDIS was returned to its own universe. (COMIC: The Continuity Cap)
