Breaking Bad to Doctor Who (1996) [pilot only]
5 connections
Breaking Bad
The X-Files
Breaking Bad characters rented cars from the Lariat Rent-A-Car which Mulder and Scully frequently rented from on X-Files.
Buffy the Vampire Slayer
The X-Files? Cigarette Smoking Man and Buffy the Vampire Slayer's Spike both smoked Morley cigarettes.
Angel
Angel was a spin-off of Buffy the Vampire Slayer
Red Dwarf
In the Red Dwarf episode "Psirens", the crew of the Red Dwarf come across a space ship graveyard which includes a Weyland-Utani ship, connecting it with Angel.
Doctor Who (1996) [pilot only]