Joseph Lockard "Lock" Martin Jr. (October 12, 1916 – January 19, 1959) was an American performer afflicted with gigantism.

[1] Martin would eventually grow to over 7 feet tall by adulthood, though his exact height was reported inconsistently.

[3] Despite his size, he had difficulty moving in the heavy robot suit, and during scenes in which he was supposed to lift and carry either Patricia Neal or Michael Rennie, they were either held up by wires, or replaced with lightweight dummies.

[2] Martin traveled with Spike Jones and His City Slickers and appeared on their television show in the early 1950s.

Towards the end of his career, he was filmed for a part in The Incredible Shrinking Man as a circus giant, but his scenes were deleted.