Mary Wells, afterwards Mrs. Sumbel (16 December 1762 – 23 January 1829), was an English actress.
She was the daughter of Thomas Davies, a carver and gilder in Birmingham, and was born there on 16 December 1762. Her father died in a madhouse while she was a small child. Her mother kept a tavern frequented by actors, and among others by Richard Yates, under whose management Mary appeared at the Birmingham Theatre as the young Duke of York in Richard III, playing subsequently Cupid in William Whitehead's Trip to Scotland, and Arthur in King John. After visiting Bath and York she went to Gloucester, where she played Juliet to the Romeo of an actor named Wells, to whom she was married in St. Chad's Church, Shrewsbury. Wells shortly afterwards deserted her.
On 1 June 1781, as Madge in Isaac Bickerstaffe's Love in a Village and Mrs. Cadwallader in Samuel Foote's Author, she made her first appearance at the Haymarket. John Genest says that she was excellent in both characters. Jenny in Lionel and Clarissa (Bickerstaffe) followed, and on 3 September in John O'Keeffe's Agreeable Surprise she was the first Cowslip, a name that stuck to her (though she is occasionally spoken of as ‘Becky’ Wells). Genest wrote that nothing could be superior to her acting as Cowslip and that of John Edwin as Lingo.
On 25 September, as Nancy in Love in a Camp, she made her first appearance at Drury Lane, where also she played on 29 October. Jenny in the Gentle Shepherd, adapted from Allan Ramsay by Richard Tickell. Harriet in the Jealous Wife, Widow O'Grady in the Irish Widow, Flora in She Would and She Would Not (Colley Cibber), and Jacintha in the Suspicious Husband followed. At the Haymarket in 1782 her name appears to Molly in the English Merchant and Bridget in the Chapter of Accidents (Sophia Lee). She also, as she says, replaced Mrs. Cargill, who had eloped, as Macheath in the Beggar's Opera, with the male characters played by women and vice versa. She made a distinguished success, and was received with great enthusiasm. She played at Drury Lane Kitty Pry in The Lying Valet, and Jane Shore on 30 April 1783, her first appearance in tragedy. At the Haymarket she was on 6 July 1784 the original Fanny in Elizabeth Inchbald's Mogul's Tale, on 6 September the first Maud in O'Keeffe's Peeping Tom, the eponymous Isabella, and Lady Randolph in Douglas.