In January 2013, it was announced that Showtime had made a series commitment for the project. Logan and Mendes previously wrote and directed Skyfall respectively. Production is set to begin in London in the second half of 2013. Showtime president David Nevins stated that the tone of the ensemble series will be "very realistic and very grounded, not Bela Lugosi. All exist in human form in turn-of-century London." Logan, a lifelong fan of literary monsters, wrote the project on spec and will script every episode of the series. It was intended that Mendes would direct episodes, but scheduling prevented this.
In May 2013, Juan Antonio Bayona announced that he would be working on the series as director, with production commencing in September 2013. Bayona will direct the first two episodes of the first series, which will consist of eight episodes.
In March 2013, it was announced that the series would be filmed in the United Kingdom; eyeing the new UK tax credit for high-end TV productions that offers a 25% rebate however, it was reported in August that production would instead take place in Bray's Ardmore Studios and other locations around Dublin, Ireland, because of the country's section 481 tax incentives. Filming began on 7 October and will last 5 months. Reports indicate that the change was made as no stage space of a sufficient caliber was available due to the filming of major motion pictures in London.
In December 2013, Showtime announced its first-ever production blog for a series with the launch of The Penny Dreadful Production Blog. The venue will give viewers an online behind-the-scenes look at the series' production from its early stages of filming in Ireland through the end of the first season, featuring interviews with cast and crew. The blog has its own website and the videos will also be released on YouTube.