Malcolm McDowell (“A Clockwork Orange”) stars in the 2012 update of “The Philadelphia Experiment” (8 p.m. Saturday, Syfy). When scientists experiment on a device to hide a naval ship, they inadvertently rediscover a vessel hidden by a similar experiment in 1943, as World War II raged. How has the unseen crew been cooling its heels for nearly 70 years?

Look for Gina Holden (“Fantastic Four”) and Nicholas Lea (“Supernatural”). Michael Pare, who starred in the original film from 1984, makes a cameo appearance.

• Wisecracking Fred Figglehorn heads to camp and yet another sequel in “Fred 3: Camp Fred” (7 p.m. Saturday, Nickelodeon). At first he believes his mother has enrolled him in the world’s dreariest summer camp, until he discovers that making new friends is really on the agenda. Look for Tom Arnold as Floyd, the camp director, in this gentle summer distraction.

• With the eyes of the world turned toward the London Olympics, BBC America invites viewers to catch up with a British television tradition.

A season five “Doctor Who” marathon (5 a.m. to 5 p.m. Saturday) unspools all day, reintroducing viewers to the latest incarnation of the decades-old fantasy, now starring Matt Smith in the title role.

If there’s an American equivalent to “Doctor Who,” it’s probably “Star Trek” and its many incarnations. And nobody represents that American series like William Shatner, star of “William Shatner’s Get a Life!” (7 p.m. Saturday, EPIX). In this film, Shatner examines the “Trek” phenomenon, its diehard fans and his own off-and-on affection for Captain James T. Kirk.

• Meanwhile, two similarly themed installments of “The Nerdist” (Saturday, BBC America) touch upon the subjects of Comic-Con (8 p.m.) and toys and games (9 p.m.).

Saturday’s other highlights

• Keri Russell, Skeet Ulrich and Mare Winningham star in the 2005 period drama “The Magic of Ordinary Days” (6 p.m., Hallmark), about the life of an unwed mother in wartime and the kindness of strangers.

• Talking a would-be suicide off the ledge on “NYC 22” (5 p.m., CBS,).

• Swimming, gymnastics and beach volleyball dominate prime-time coverage of the Summer Olympics (7 p.m., NBC).