If they stuck with the B story (two races of fish monsters who hate each other are both being escorted to a peace conference) then this wouldn’t be so bad. But that story was told in the Original Series. Instead we’re fed some story that warps from lame to kinda dumb to unbearably asinine.
The lameness is when some “energy mass” infects the ship’s computers (yeah, seen this before, haven’t we?) and then temporarily possesses members of the crew. Since that old saw might seem a little dull, some genius decided it was a good idea for Data to fall in love with Sherlock Holmes. Yes, seeing Brent Spiner in whiteface cry “Indubitably!” over and over again is my idea of fun. We end with Picard being zapped out into space as pure energy, but somehow he swims back to the ship, inhabits the soul of the computer, goes back in time a few minutes, recreates his solid form with the transporter and then — doesn’t remember a thing. I remember enough to say This Episode Blows.