Giles (plaintiff) was an elevator operator for an elevator maintained by Otis (defendant). While ascending in the elevator, Giles noticed that the elevator compensation chain had swayed too far and failed. Unable to reach the chain from the inside of the elevator, Giles sustained injuries when the elevator cabin shook due to the chain’s failure. Giles reversed the elevator’s direction in order to exit at the nearest floor. The elevator’s parts, including the compensation chain, were maintained exclusively by Otis. Giles brought a claim of negligence against Otis, requesting the application of the res ipsa loquitur doctrine. A witness for Otis testified that for the compensation chain to sway excessively, Giles must have misoperated the elevator, probably by rapidly reversing the elevator’s direction. Giles testified that she only reversed direction after the chain had failed. The trial court did not apply res ipsa loquitur and granted Otis’s motion for a directed verdict. On appeal, Otis argued that res ipsa loquitur should not apply, as Giles had control over the chain sway at the time of the accident. The Appellate Court reversed the trial court, finding that Giles had presented enough evidence to submit the issue of negligence to the jury under the res ipsa loquitur doctrine.