Sam & Max 303: They Stole Max's Brain! is the third episode of the third Sam & Max season named Sam & Max: The Devil's Playhouse. After the happenings of the second episode and a bathroom break Sam makes a horrible discovery: someone stole Max's brain! Of course he immediately searches for the culprits which turn out to be the main villains of the first two episodes...
Max's psychic powers once again play an important part. Besides teleporting and predicting the future, which are known from the first episode, there also is a new one: Max can shapeshift into items which are shown in a picture, e.g. on a poster.
The rest of the gameplay is similar to the former seasons: the player walks through the levels, collects items and uses them to solve puzzles. Dialogues are a ring menu similar to Mass Effect where the player only chooses the topic instead of the whole sentence. Unlike traditional adventure games the movement of Sam is not controlled by point & click but by holding the left mouse button and dragging the mouse in the desired direction (or alternatively with the keyboard keys). Interactions with items or persons are carried out with a single mouse button.
Like the Tales of Monkey Island series single episodes weren't available for purchase at the initial release. Users were required to buy the five episodes as a whole as they are released on a monthly basis.