Brad Pitt, Johnny Depp and Jude Law's Retro-Style Sunglasses (Cannes 2011)

Three's a trend! It looks like the hottest style of men's sunglasses for spring are transparent: Brad Pitt, Johnny Depp and Jude Law were all seen in see-through lenses at the 64th Cannes Film Festival.

Pitt greeted fans and press at the Tree of Life photocall Monday in dark brown tortoiseshell frames with light honey-tinted lenses by Tom Ford. The rectangular "Singleman" style was inspired by Colin Firth's character, George Falconer, in the 2009 film A Single Man, which Tom Ford directed.

Pitt was the essence of cool when he later slipped into a shawl-lapel tuxedo and dressier black acetate frames with transparent lenses by Tom Ford for the film’s star-studded red carpet premiere.

Depp, who's known for his distinctive style, wore metal aviators with edgy blue-tinted lenses for a daytime photocall Saturday. For the Pirates of the Caribbean: On Stranger Tides premiere, the actor arrived in black-and-white formal attire with retro-looking dark transparent shades by Moscot. Depp's "Lemtosh" style by the NYC-based eyewear company is a throwback to a frame that was popular in the 1930s and 1940s ($225-$255). Buddy Holly and Truman Capote were a few of the original "Lemtosh" wearers.

Law also made a bold statement in black acetate frames with semi-transparent gradient lenses when he arrived at Nice Airport in France on May 10. The British actor and film fest judge was spotted wearing the same shades at the London Film Festival cocktail party in Cannes on Sunday. Other fans of the transparent style include Bradley Cooper (Ray-Ban) and Robert Downey Jr. (Oliver Peoples).

So much for shielding eyes from the paparazzi behind dark shades -- this season it's about being seen.