Context: Bob and Doug McKenzie (Rick Moranis and Dave Thomas) are two dim-witted and unemployed "hosers" living in Toronto, Ontario who find themselves in a bind when they squander their father's beer money and then run out of beer. The brothers place a live mouse in a beer bottle in an attempt to blackmail the local beer store into giving them free Elsinore beer, but are told to take up the matter at the Elsinore brewery instead. After presenting the mouse to management at the brewery, the brothers are given jobs on the bottling line inspecting the bottles for mice. They take this opportunity to drink lots of free beer off the line; later, they present their parents with a van full of free Elsinore beer products as part of their payment with their new jobs.Meanwhile, the evil owner of the brewery, Brewmeister "B.M." Smith (Max von Sydow), is perfecting a secret plan to take over the world by placing a mind-control drug in Elsinore beer which, while rendering the consumer docile, also makes him or her attack others when stimulated by certain musical tones. Smith tests this adulterated beer on patients of the conveniently located Royal Canadian Institute for the Mentally Insane, which is connected by underground tunnels to the brewery. The effects of the tainted beer are demonstrated in an extended sequence during which the mental patients don armored Star Wars-style hockey garb and, after consuming the beer, respond to synthesizer music by variously playing hockey, skating together in sync, and brawling on the ice.It seems the former brewery owner John Elsinore has recently died under mysterious circumstances and his daughter, Pam (Lynne Griffin), having recently turned 21, has been given full control of the Elsinore brewery. Pam's incompetent uncle Claude (Paul Dooley), in the interim, had married her widowed mother and is reluctant to give up his recently-gained control of the brewery. The reason for this is further revealed to be that the bumbling Claude is collaborating with Brewmeister Smith, for whom he is a buffoonish toady, providing a cover for the Brewmeister's nefarious plans. Bob and Doug blunder into the midst of these plans when they rescue Pam from a malfunctioning security gate and both become fast friends with her.While exploring the massive brewery, Bob and Doug find a shuttered cafeteria containing an old Galactic Border Patrol video game that supernaturally reveals that Brewmeister Smith murdered John Elsinore and that Uncle Claude was deeply involved. Additionally, while poking around the brewery, Bob and Doug meet a one time hockey great, Jean "Rosie" LeRose (Angus MacInnes), whom Bob recognizes from the hockey card he has back home at his parents' house. Having suffered a career-ending nervous breakdown and fallen under Smith's control, Rosie gets locked up at the insane asylum but is determined to fight against the Brewmeister's plot for world domination.Eventually, Bob and Doug wander into Brewmeister's operations room while he is away, and Doug takes a record disk of John Elsinore's murder, believing that it is a New Wave bootleg record. Immediately afterward, Brewmeister and Claude shoot the brothers with tranquilizers. They then dress up in the brothers clothes where they are shown on security camera shooting tranquilizer darts at Pam and a friendly associate, named Henry Green, and put their unconcious bodies in kegs.When Bob and Doug wake up, they are back in their van, convinced that their suspicious discoveries were all just dreams, and they are instructed by Claude to deliver two kegs of beer (actually containing an unconscious Pam and her father's friend, Henry Green) to a party at the bottom of a big hill. However, the brakes have been modified to only allow two stops before giving out altogether.Nevertheless, as Bob and Doug drive, they soon get distracted and decide to stop off at their house to feed their dog. They also leave behind the incriminating record disk of Brewmeister and Claude's actions at their house. Having wasted one stop prior, they find themselves unable to stop the now-speeding vehicle and eventually wind up jumping off of the Toronto pier into Lake Ontario. Rosie arrives and tries to rescue Pam who 
 Question: What is the brewery is connected to the mental institute by?
Output: underground tunnels