Papers of Gwyn Thomas, comprising autobiographical material, [c. 1946]-[c. 1972]; drafts, typescripts, notebooks and photocopies of novels and stories, [c. 1935]-1974; plays, including reviews of plays, [1940s]-1978; essays, articles and lectures by or about GT, 1926-1985; scripts for radio and television, including tributes to GT 1948-1988; book reviews, 1961-1971; professional and personal correspondence of GT and occasionally other family members, 1931-1985; letters to and from his wife, Lyn Thomas, after his death, 1981-1984; cuttings, 1937-1986; photographs; miscellaneous personal and literary papers [post-1913]-1984; notebooks [c. 1935]-[1970s]; and material collected by GT's biographer, Michael Parnell, including drafts and notes for the biography, notes , articles and correspondence on GT and his works, [c. 1984]-1989. Further manuscripts comprise a notebook, typescripts of two plays and letters.

Papers and memorabilia documenting the career of Sir Harry Secombe CBE, the entertainer, comedian, singer, star of film, radio, television and theatre, also a writer and broadcaster. This collection was compiled by Harry himself, together with his wife Myra and their children. The papers include scripts from stage, radio and television shows such as "The Goon Show", "Pickwick" (1963 and 1993), "Harry Secombe Show", "Secombe and Friends", "Sunday Night at the London Palladium", etc.. Book manuscripts including "Twice Brightly" (1974), "Goon Abroad" (1982), "Arias and Raspberries" (1989), and "Strawberries and Cheam" (1998). Many anecdotes and speech notes; magazine articles in draft and published; programmes and posters (many signed); letters, personalia, honours, awards ephemera, charity work, funeral and memorial service. Harry was well known for his humorous cartoons and caricatures which feature throughout the collection.
The large collection of personal and publicity photographs, including "Pickwick" productions, "Oliver!", together with stars of theatre, television, friends, and Royalty have been transferred to NLW photographic collections.
Three paintings have been transferred to NLW framed works.

Papers relating to and created by Margiad Evans (Peggy Eileen Whistler), [1930s]-[1958x1965], comprising material for an unpublished critical biography of Margiad Evans, compiled by W. Arnold Thorpe, [1936x1965], including transcripts by Thorpe of poems, prose and letters by Margiad Evans, scripts of radio broadcasts and extracts of reviews of Margiad Evans's published prose works; correspondence relating to information on Margiad Evans; biographical and related material; Whistler family photographs; notes by W. Arnold Thorpe and source material; together with manuscripts and papers of Margiad Evans, including drafts and copies of poems, some unpublished [c. 1945]-[1958]; unpublished and published prose works, [c. 1930s]-[1958]; notebooks and journals, which include drafts of poems and prose pieces, 1942-[1950s]; correspondence, mainly from Margiad Evans to her husband, 1934-1958; reviews of Autobiography and A Ray of Darkness[1943-1952]; drawings including drawings representing eighteen out of the thirty illustrations for Alfred Williams, Tales from the Panchatantra (Oxford, 1930); and family papers, 1939-[1950s].

Additional papers donated October 2021: see added Series.