'The Tears Of Uther Pendragon: Part 1', the first episode of series three which saw Merlin saved by the Dragon Lord, averaged 5.58m (24.2%) between 7.25pm and 8.10pm.
Saturday night's opener was 500k up on last year's second series premiere rating for the family drama - despite airing against The X Factor.
Louis Walsh's spat with Pixie Lott on this week's auditions round was seen by a total of 10.9m (45%) - 10.45m (43.1%) on ITV1, and 449k (1.9%) on HD from 7.45pm - holding exactly the same audience amount week-on-week. The Xtra Factor followed at 9pm with 1.19m (5.4%) for ITV2, and 208k on timeshift.
Strictly Come Dancing's special launch show was less popular, with 7.07m (37.5%). However, the audience eventually climbed from 5.94m (33.6%) at 6.25pm to a peak of 8.02m (38.5%) at 7.15pm.
Over on ITV1, a new series of All Star Family Fortunes put in 4.26m (20.7%). Before that, Animals Do The Funniest Things amused 2.24m (13.4%), pipped by a Tonight's The Night compilation show which entertained 2.61m (17.7%).
Post-X Factor, new adventure series 71 Degrees North found a decent audience on its first night: 4.57m (20.9%) on ITV1 and 254k (1.3%) on HD. Last Night At The Proms appealed to 3.67m (17.5%) between 9.10pm and 10.40pm.
Earlier Proms coverage managed 1.27m (5.4%) for BBC Two, after which 1.71m (7.9%) and 1.39m (6.7%) caught repeats of Have I Got News For You and Mock The Week. Later with Jools Holland picked up 910k (5.7%).
Elsewhere, a screening of 9/11: State Of Emergency brought in 2.17m (10.1%) on Channel 4, and 356k on timeshift. Witness followed with 727k (5.7%) at 10.15pm. Over on Five, NCIS interested 1.08m (4.5%) at 8.15pm, then a double bill of CSI found respective audiences of 1.32m (6.1%) and 1.03m (5.4%).
Overall, ITV eclipsed BBC One in primetime, with 26.5% (HD: 1.1%) to 21.6%. Channel 4 was third with 6.6% (+1: 0.9%), BBC Two followed with 6.1%, and 4.7% put Five in last place.
BARB ratings data supplied by Attentional