Kate Mulgrew in Mrs. Columbo (1979)

Before she was Janeway on Star Trek: Voyager (1995) Kate Mulgrew played Lt. Columbo's crime solving, reporter wife in this ill conceived NBC series. It lasted for only one season, much to the pleasure of Peter Falk and Columbo creators Richard Levinson and William Link. Mulgrew played Kate Columbo, who used her investigative reporter skills to solve mysteries. Columbo himself never made an appearance in the show, but in the credit sequence below, uploaded by PIMannix you'll see his car and his dog.

The series did not do well in the ratings and was heavily tinkered with during its short run. It was retitled twice, first to Kate, The Detective, and finally to Kate Loves a Mystery. The updated credit sequence featured a new theme song and all evidence of Columbo was erased - the character was renamed Kate Callahan. Below is that new credit sequence, uploaded by robatsea2009.

Needless to say, this series has never made it to DVD, though one episode of it was included as a bonus feature in the DVD releases of the Columbo series for seasons 3, 4 and 5.

Obscurity factor: 9 (hard to find, only on DVD as bonus features, credits on YouTube)