No details of Addison's role in the two-part series finale Dark Water/Death in Heaven have yet been revealed, but Addison shared his excitement at landing the part with RadioTimes.com:
"'Would you like to be in Doctor Who?' is the easiest question I've ever been asked. It's a 35-year dream come true. Seven-year old me would be going off his nut and I'm not far behind.
"It's a great way to spend a couple of weeks, working with people I've always wanted to work with on a show I've loved all my life. My bucket list is quite a lot shorter now."This will not be the first time that Addison appears alongside new Doctor Peter Capaldi onscreen, as the two have previously worked together in political comedy The Thick of It and its spin-off film In The Loop.
Addison is also an established stand-up comedian whose other television work includes appearances on panel shows Mock the Week and Have I Got News for You. Most recently Addison starred alongside actress Jo Joyner (Lynda 'with a y', The Parting of the Ways) in Sky Living's Trying Again.
This most recent casting news means that Addison joins previously announced guest stars Michelle Gomez and Sanjeev Bhaskar in the series finale, which has been penned by lead writer and executive producer Steven Moffat and directed by Rachel Talalay.
Doctor Who returns to our screens on Saturday 23rd August with feature-length series opening episode Deep Breath.
[Source: Radio Times]