It is London, 1893. H.G. Wells (Freddie Stroma) is destined to become a famed science fiction author, but on this evening he's just a little known writer struggling to get published. He has invited his intellectual friends to show off his new invention - a time machine - but never suspects his late arriving guest, surgeon and friend John Stevenson (Josh Bowman), is the infamous Jack the Ripper. When the police arrive looking for Jack the Ripper, John sneaks into the time machine and flees to modern day Manhattan with Wells in hot pursuit. Wells arrives inside a museum exhibit featuring himself, The Man Ahead of His Time. Unrecognized by security, he's hauled off to the museum curator, Jane Walker (Genesis Rodriguez), who is attracted to this odd fellow and intrigued that the machine is warm and security videos show two different men seemingly appearing out of thin air.

Wells, meanwhile, is a complete fish out of water, always rising politely whenever Jane stands up, puzzled at everyone staring at the screens of their small devices and awestruck by the bustle and bling of Times Square. Wells must stop Jack the Ripper who needs Wells' key to the time machine so he can murder throughout the centuries with impunity. Wells manages to hold on to the key, but the Ripper slips through his fingers when Wells is knocked down by a yellow cab. As luck has it, Jane's business card is in his pocket and she is called to pick him up from the hospital. She takes H.G. to her apartment where he tells this modern independent woman that she fascinates him.

Jane is more wary, but sparks really fly after she rescues him from an electric razor he's using to shave off his 19th century facial hair. The deal is sealed when he puts on her ex's jeans and t-shirt, and transforms into a 21st century hunk. It is the cat and mouse game between Wells and Jack the Ripper that fuels the action, as Wells tries to track down John while John tries to lure Wells in order to get the key. It's only when Jack the Ripper strikes again that Wells blurts out his true identity to Jane, and proves it by taking her on a trip in the machine three days into the future where, horrified, they learn Jane will be a victim of The Ripper unless they stop him.