It’s that time of the summer doldrums when “The Bachelorette” gives way to “Bachelor Pad” (7 p.m., ABC). And if you can explain or care to understand the differences, you’re a bigger fan of this genre than I am and in serious need of better things to do with your time.
For the record, “Pad” reunites some of the most memorable and controversial veterans of “The Bachelor.” This offers proof of the enduring truth that once you appear on a reality show, you’re eminently qualified and all but destined to appear (or want to appear) on another.
And speaking of wanting to appear on a reality show, “Pad” also features five “Super Fans” who were discovered through the miracle of an open casting call. If you weren’t chosen, take heart: You’re still a “Bachelor” fan; you’re just not “Super” enough.
This group heads to the fake mansion to share space, hot tub time and connive to backstab each other in the quest for a $250,000 prize. As if chained to the mast of a shipwreck of tedium, Chris Harrison returns as your host.
l “Alphas” (9 p.m., Syfy) returns for a second season, starring David Strathairn as the scientist den mother for a pack of seemingly ordinary folk with super-amazing powers. This season promises a raft of new guest stars. Look for Sean Astin (“The Lord of the Rings” series), C. Thomas Howell (“Southland”), Lauren Holly (“NCIS”), Steve Byers (“Total Recall”), Kandyse McClure (“Battlestar Galactica”) and Noah Reid (“Rookie Blue”).
“Warehouse 13” (8 p.m., Syfy) also returns. Brent Spiner (“Star Trek: The Next Generation”) joins the fun as Brother Adrian, the leader of a furtive cult not unlike the Knights Templar. This is the fourth season of “13,” and it picks up from a season-three cliffhanger involving the destruction of the warehouse and the loss of several series favorites.
Tonight’s other highlights
l The documentary “Vito” (8 p.m., HBO) profiles Vito Russo, a pioneering activist for gay rights.
l “Unsung” (8 p.m., TV One) profiles the Motown group the Marvelettes, who never attained the fame of the Supremes or Martha and the Vandellas, in spite of hits like “Please Mr. Postman,” “Too Many Fish in the Sea” and “Don’t Mess With Bill.”
l The oddly named “Market Warriors” (8 p.m., PBS, check local listings) goes in search of antiques in Philadelphia.