The Cooler (2003)

Romantic drama starring William H. Macy as Bernie Lootz, a lonely middle-aged man with terrible luck who owes the Shangri-La casino in Las Vegas, owned by old-fashioned mob boss Shelly Kaplow (Alec Baldwin), over $100 000. To repay his debt, he works for Shelly as a 'cooler' - someone who plays alongside high rollers to stop them from winning too much. His life takes a turn for the better when he falls in love with cocktail waitress Natalie (Maria Bello), and he experiences real happiness for the first time in years. But when his luck starts to spill over onto the gambling floor, Shelly is none too impressed, and sets out to sabotage the most important thing in Bernie's life: his relationship with Natalie.