Preternatural Research Bureau

From TARDIS Index File, the free Doctor Who reference.

Preternatural Research Bureau or P.R.O.B.E. was an organisation investigating paranormal activities.

Liz Shaw spent some time working with P.R.O.B.E. after leaving UNIT. (BBV: The Zero Imperative and others)

[edit] Behind the scenes

P.R.O.B.E. was introduced in a series of independent films produced by BBV Productions, which featured Liz Shaw from the Doctor Who series. Although considered unofficial, and not aimed for broadcast on television, this series of films nonetheless constituted the first ongoing spin-off set in the Doctor Who universe, predating the similarly themed Torchwood by more than a decade.