It's the last week of heats, and another four ambitious chefs go all out to impress Marcus, Monica and Gregg as their race for the title begins. First, they must prove themselves in the infamous Skills Test, followed by the Signature Menu round which offers them a chance to put their own stamp on the competition.Up first is Monica's Skills Test, and tonight she challenges two chefs to make crispy squid croquettes served with a garlic mayonnaise. Preparing the squid from scratch is only half the battle, and only those who remain calm will stand any chance of delivering a perfectly cooked seafood treat that delivers a true taste sensation.The last two chefs are tasked by Marcus to make a sweetbread and caramelised onion tart served with a meat stock vinaigrette. There can be no excuses as, with the pastry case already provided, Marcus will expect every element to be bang on the money. Tender sweetbreads, rich, succulent onions and a punchy dressing - anything less will fall short.Finally, the four chefs have one last chance to win over the judges as they deliver their Signature Menu – two courses that represent them in the best possible light, and taste as good as they look. Any mistakes could cost them their place in the competition.Only the best chefs on the day will move forward to the last quarter-final as the race for the MasterChef: The Professionals title continues.