Star Trek: The Next Generation: A Hard Rain

Captain Jean-Luc Picard has long enjoyed playing the part of Dixon Hill, a hard-boiled private eye straight out of American pulpfiction. His holographic excursions into 1940s San Francisco, a colorful world of gunplay and gangsters, provide a welcome diversion from his hefty responsibilities as a Starfleet captain.
But not this time.

The Starship Enterprise™ has lost power and control, its own momentum carrying it ever deeper into a dangerous zone of warped space and time. And the only way out is hidden somewhere in the mean streets and back alleys of old Frisco. But so is a cold-blooded murderer....

Now Dixon Hill, alias Jean-Luc Picard, must get to the bottom of a tangled mystery that threatens the lives of everyone aboard the Enterprise !