Attention: Chrome users have reported an issue with the website displaying the thumbnails when viewing films. Unfortunately this is an isolated problem with Chrome. Reports show this is occurring on many websites across the web.
Until such a time we can find a fix for this we advise you use browsers such as Firefox or Safari. The videos will still appear and play in Chrome but the thumbnail is in a blank space - click the blank space to reveal the video.
Alternatively deleting your Cache data within Chromes settings can sometimes help.