Twelve of the missing episodes from the first series of classic TV show The Avengers are to be turned into full-cast audio productions by Big Finish, it was announced today.

Created by Sydney Newman and starring Ian Hendry as Dr David Keel and Patrick Macnee as John Steed, the show began airing on Saturday 7th January 1961 with the episode Hot Snow. However, only the first 20 minutes of that story plus two full instalments from the rest of the 26-episode run - Girl on the Trapeze (which did not feature Steed) and The Frighteners - have survived.

But now, after signing a licensing deal with Studio Canal, Big Finish is to work from the surviving scripts to present adaptations of a dozen of those lost episodes in three four-disc box sets. The scripts will be adapted, with minimal changes, by John Dorney. The director will be Ken Bentley, with executive producer duties going to Nicholas Briggs and Jason Haigh-Ellery.

Producer David Richardson said: The roles of Keel and Steed have already been cast, with "two brilliant, high-profile actors" playing them, he added. A casting announcement will be made once recording begins next month.

John Rodden, the general manager for home entertainment at Studio Canal, said: Volume 1 of The Avengers: The Lost Episodes, which will include a full re-creation of Hot Snow, will be released in January 2014, with Volumes 2 and 3 following in July 2014 and January 2015 respectively.

The titles of the episodes selected for recording are yet to be announced.

The acting talent of cult star Patrick McGoohan is to be celebrated by the BFI with a season of his TV and film work.

Taking place throughout August this year, Patrick McGoohan: A Genuine Original will see screenings ranging from the Armchair Theatre episode The Man Out There – which originally aired on 12th March 1961 and saw McGoohan playing a cosmonaut, Nicholai Soloviov, who is trapped while in orbit – to rare footage relating to probably his most famous and iconic role: that of The Prisoner, which was first broadcast between September 1967 and February 1968.

Other gems will include two episodes from the 1960s series Danger Man, in which he played secret agent John Drake, plus his stage appearance in the Ibsen play Brand, filmed by the BBC and shown on 11th August 1959.

The BFI said:
Born in America but brought up in Ireland and Britain, McGoohan started his career backstage at the Sheffield Playhouse Theatre, and before long he was making on-stage appearances, proving to be a natural. During the 1950s, he appeared in several productions in London's West End, where he was spotted by Orson Welles, who then cast him as Starbuck in his production of his self-penned drama Moby Dick-Rehearsed at the Duke of York's Theatre in the summer of 1955.

McGoohan's first film appearance was as an uncredited RAF guard outside the briefing room in the 1955 feature The Dam Busters, and he went on to appear in many movies, including the critically-acclaimed and Oscar-nominated Ice Station Zebra (also being shown during this season) in 1968, the 1981 sci-fi/horror Scanners, and 1995's Oscar-winning Braveheart.

Aside from Danger Man and The Prisoner, he starred in the TV series Rafferty, in which he played a retired army doctor who had moved into private practice, and he had a lengthy association with the detective series Columbo, for which he received two Emmys. McGoohan also received a BAFTA for an earlier appearance in the Armchair Theatre anthology series. He died in January 2009, aged 80.

Tickets to all the screenings go on public sale on Tuesday 9th July.

The second in the special Missing Believed Wiped events at the BFI this year will feature hitherto-unseen recoveries from ITV.

Taking place on Friday 2nd August at 6.20pm, the main presentation is an instalment of ATV's variety show Saturday Spectacular. Originally broadcast on 11th July 1959, it showcased the American singer Jo Stafford, who was the first woman to top the UK singles chart, reaching number one in January 1953 with You Belong To Me.

Stafford had an eponymous TV show in the USA in 1954 and would go on to have a similarly-titled UK series, again on ATV, in 1961 – and whose first edition included a poetry-reading Claire Bloom among its guests.

The 1959 edition of The Jo Stafford Show being shown by the BFI also features entertainer Teddy Johnson and was directed by Bill Ward. It came to the organisation's attention early this year via a private collector.

The BFI says: Among the other light-entertainment treats being shown from the same collection will be the closing 20 minutes of a 1950s Diana Dors Show.

Stafford died in July 2008, aged 90, while Dors - who was married to the actor Alan Lake - died in May 1984 at the age of 52.

The BFI is celebrating 20 years of its initiative to locate and screen lost items of British TV with a series of Missing Believed Wiped events this year. The first one, held last month, showed gems from the collection of TV cameraman and director of photography John Henshall.