1. The fact you are using a laptop means there is a high chance the game is putting a strain on it, that is probably the problem.
2. Are the fans working? If not, that may be the problem. Also, is the laptop hot/overheating?
3. Try repairing M&B from steam, if not re-download.
4. If you have any other games with equal demand(aka NOT Crysis 3, that has advanced graphics so higher demand), see if the same thing happens with them. If so, it might be your computer. If not, probably the game itself.
P.S. Would you mind posting your computer specs, aka information about it likes graphics card, operating system(windows xp, windows 7, windows 8), computer model, year made etc? That would help. So would any other information.
P.S.S. If you need anything, feel free to PM me.