This Monday's episode, "Dueling Pistols/Evelyn Nesbit Portrait/Little Big Horn Bayonet," follows the standard format: three investigations of three objects conducted by one or two of HD's quartet of historians. Some episodes are grouped by a theme such as last week's about the site of what might be the first movie studio, a lighter that suggests a connection between a Hollywood film mogul and a Nazi propaganda studio, and what may be the camera used to film King Kong (catch the repeat at 3 a.m. Saturday...or TiVo it). But if the promise to learn about this week's items (pistols that may have been used in the last American duel; illustrator Howard Chandler Christy; and a bayonet that may have survived the battle of Little Big Horn) isn't enough to make you tune in, then maybe the Texas episode debuting July 26 will be. Dallas takes the spotlight with an inquiry about whether Dallas' downtown railroad station was the first in Texas. The other two explorations take the detectives to San Antonio and Texas City. It will be cool, even if we're not.