WHO DO YOU THINK YOU ARE?, BBC1, 8pm

TONIGHT’S subject is Lulu.

Born in Glasgow in 1948, she came of age in the swinging 60s, when pop culture was in its glory and the city was still a smoky, clattering powerhouse.

Forget the usual scenes this series throws up of tearful celebs getting emotional because granny was a servant or grandad worked in the mines — this episode actually has some genuinely good stories and revelations.

The main mystery which knots the branches of Lulu’s family tree is why her mother was given up for adoption. Her mum was one of seven siblings, and was the only child who was given away, so why her? Lulu goes back to Glasgow to find out what happened to make a mother surrender one child but keep the other six.

The horrible sectarian divide also touched Lulu’s family, with her Catholic grandad and her Protestant gran struggling to marry across the religious chasm.

TOP OF THE LAKE, BBC2, 9pm

THIS week’s episode continues the utterly bonkers theme.

“I’m gazing into the abyss and I’m going to keep gazing until the abyss gazes back.” That’s the type of crazy dialogue you’ll be treated to tonight. I’m starting to enjoy this show because I’m watching it as a comedy, not a thriller.

Mary turns 18, and Puss tells her she’s now old enough to work beside her “sisters” in the brothel. If she cares about feminism and equality, he says, she’ll do it. The brothel workers are horrified and won’t permit it, so Puss has other plans for the pathetic little Mary.

He also insists on gate-crashing her school’s daddy-daughter dance where he invades the dance floor in a hideous sleazy waltz.

And a heartbroken nerd phones the police to say he might know the identity of “China Girl”, and tells them to check up on Alexander. It dawns on Robin that this man is her daughter’s lover, and that the brothel may be selling sex work and surrogacy.