It is a gluten-free beer that is said to fuse the “legendary character” of Theakston’s Old Peculier with the hop-charged attitude of Rooster’s Baby-Faced Assassin.
Launching at the end of May in cask, keg and can, the limited-edition 5.4% ABV release will debut at Theakston’s flagship pub, the Black Bull in Paradise and Rooster’s Taproom in Harrogate before rolling out to pubs, bars and retailers across the UK.
A joint statement explained: “Peculier Assassin is what happens when two distinctive Yorkshire beers collide. Rich, dark and fruit-laden Old Peculier meets the tropical punch and resinous hop hit of Baby-Faced Assassin to create something entirely new – a smooth, deep ruby-brown beer layered with roasted malt sweetness, juicy citrus and pine notes, balanced by vibrant bitterness and a long, effortlessly drinkable finish.”
Old Peculier is the flagship beer of Theakston that is dark, ruby red in colour, and is said to have cherry fruit character, soft banana esters and rich malt backbone, layered with gentle roasted complexity.
Decades old connection
Its name is taken from the ancient ecclesiastical Court of the Peculier, a rare form of church jurisdiction that is claimed to “reflect the beer’s own independent Yorkshire spirit and long-standing sense of character”.
Meanwhile, Baby-Faced Assassin, a 100% Citra-hopped American-style IPA was initially conceived as a 25-litre batch homebrew recipe before forming part of the Rooster’s core range in 2013. First canned in 2014, the beer has since won plenty of awards during the past decade at competitions and beer festivals across the UK and abroad.
The connection between the breweries stretches back decades, with Rooster’s chairman Ian Fozard involved in the 1980s CAMRA campaign that supported Theakston’s return to independent ownership. Years later, the two Yorkshire breweries have come together for a collaboration that blends Theakston’s renowned cask ale heritage with Rooster’s pioneering use of American hops.
The beer has been jointly developed by Theakston head brewer Mark Slater and Rooster’s head brewer Oliver Fozard.
Great fun
Fozard said: “Mark and I have known each other within the industry for more than 10 years so it’s been great fun to work with him on this project. From our initial meetings there was only one beer we were both keen to explore so I’m delighted with how both breweries have come together to create Peculier Assassin.”
Slater added: “Working with Oliver on Peculier Assassin has been a really enjoyable process. We both came to the table with a clear idea of what we wanted to achieve – bringing together the richness and depth of Old Peculier with the bright, modern hop character Rooster’s are known for. It’s been a genuine collaboration throughout, and I’m really pleased with how the beer has come together – it feels balanced, distinctive and full of character.”
Theakston chairman Simon Theakston said: “The combined brewing skills of Mark and Oliver ensure this collaboration is a real success and a toast to independent breweries born and bred here in god’s own county.”
Rooster’s chairman Ian Fozard added: “Both breweries have always done things their own way, so this collaboration felt incredibly natural from the outset. The result is an exciting, bold and intriguing beer that’s been enormous fun to brew.”
Theakston has brewed the cask version of the beer, while Rooster’s has produced the keg and can releases.

