The Smithsonian Magazine reviews a direct-to-video release of Sherlock Holmes timed to capitalize on the blockbuster starring Robert Downey Jr. In the cheap version, Holmes and Watson battle "Spring-Heeled Jack," who turns out to be a mechanical (and miniature) Tyrannosaurus, which

violently interrupts a business transaction between a prostitute and a client in the infamous Whitechapel district of London which “Jack the Ripper” prowled. While the actual case was much more convoluted, so much so that the killer has never been conclusively identified, in the film it is clear that at least one of the notorious Whitechapel murders was carried about by a robotic Tyrannosaurus.

Strangely, the magazine states that the movie is set in 1882, six years before the Ripper. The movie stars Dominic Keating and Gareth David-Lloyd.

I would still plump for Nessie over a T-Rex.