Sam is missing!
Pick up the RADIO from the counter (10/10). On the floor is a gum with a dime in it. Pick it up. It’s stuck (1/11). Open the double doors and go through. You’ll meet Guybrush (1/12). Talk to Guybrush about everything (2/14). Use the door behind Guybrush and go through to meet LeChuck (1/15). Talk to him (2/17) and he knows where to find Sam. He locked him up and won’t give you the key.
Return to the room with Guybrush and talk to him again. Ask him to help you and if he can kill him for you. He’ll ask for a sword and even with that isn’t prepared to help you. Tell him you’ll do it yourself and blame him and then he’s willing to kill LeChuck as long as you provide the sword. Walk back to the left and from the hall open the door with ‘Office’ on it and go through (1/18). In the corner of the room is a sword. Look at the sword (1/19) and pick it up the SWORD (10/29).
Walk back to the left and go through the double doors. Give the sword to Guybrush and he’ll take care of LeChuck (10/39). In return you’ll get the KEY. Walk through the door behind Guybrush and use the key on the door on the right. Use the door to open it and then go through to find your friend (10/49)
Game source: A copy of the game was found here on the internet.