You’re working late in the laboratory one night, hard at work on your latest hypothesis. You stretch, and take a glance at the clock. Ooh, if you don’t leave now you’ll feel awful in the morning. You lock up and get ready to head home.

 You’re in the farthest lab from the exit. As you enter the hallway, you find the doors locked. Did they forget you were here and shut the place? Egads, what a blunder! You’ll have to leave using the secret tunnel!

Can you pass the seven locks of the science secret tunnel, and get home in time for a good night’s rest?

P.S. Feel free to ask for help or use a search engine like Google.