With stolen pistols and horses, and their faces hidden by Venetian masks, Plunkett and MacLaine had a short but highly successful career as outlaws.
Plunkett is supposed to have encouraged MacLaine by telling him that they had a right to live, but that the means were not available to them unless they overcame a few scruples and took from the improvident wealthy.
)[1] On one occasion, when taking clothes belonging to a priest (who objected), Plunkett replied that they stole because necessity obliged them to do so, not from wantonness: and on another, he put aside his pistol while robbing a lady because he saw she was alarmed by it.
In 1845, Charles Miner reported the claim that the Colonel William Plunket who commanded one of the two earliest battalions of the Northumberland Militia in Lycoming County, Pennsylvania, in 1775 was the same person as MacLaine's former accomplice.
Miner quotes from The Gentleman's Magazine for September 1750[3] to summarise the association of Plunkett with MacLaine in the attack on Lord Eglintoun on Hounslow Heath.