Little Insight on ‘Terror Network’

When the doomed epic “Heaven’s Gate” was unleashed upon an unsuspecting moviegoing public in 1980, one particularly crusty critic compared the experience of watching it to “a forced four-hour tour of your own living room.”

Tonight’s airing of a “Frontline” documentary on the Sept. 11 terrorist attacks packs a similar appeal. “Inside the Terror Network” (9 p.m., KCET) errs not in its execution but in the excruciating familiarity of most of the subject matter. Anyone who hasn’t been living in an Afghan cave for the last four months has been immersed in the minutiae of the people and places involved, so the considerable burden falls on any new working of the subject to bring something fresh to the table. This doesn’t pull that off.

The one-hour program focuses on three of the principals in the attack: Mohammed Atta, Marwan al Shehhi and Ziad Jarrah. Their shared apartment in Hamburg, Germany, serves as the documentary’s ground zero, where their increasingly radicalized beliefs crystallized into carrying out the unthinkable.

And what trip into the mind of a mass murderer would be complete without a visit to colleagues and mystified family members, who mouth all-too-familiar sentiments about the subject’s quiet charm and gentle nature. Until they began changing, that is.

On Sept. 11, everything changed.