After Martha Jones leaves the Tardis, the Tenth Doctor encounters his former self. As his former self figures out who he is the Tenth rambles on about how much he loved being that incarnation. The Fifth Doctor disappears back to his own time as the Titanic crashes into the Tardis leading into the next story 'Voyage of the Damned'.
Doctor Who: Time Crash
The Tenth Doctor meets one of his previous incarnations.
