ONE minute you’re down on one knee proposing marriage, the next you’re down on all fours gasping for breath. Fortunately, Rita gets out of the way swiftly and doesn’t end up trapped under Colin when he collapses in a heap on the floor.

Actually, that last bit isn’t true.

Several days elapse between the proposal and the collapse in Coronation Street (ITV1), but I reckon Rita needs a bit of excitement in her life.

She gets that in the Rovers as Colin Grimshaw – with the accent on grim – gathers his loved ones around him to celebrate his 70th birthday.

He surprises Rita, which is pretty difficult to achieve for a woman who was nearly run down by a Blackpool tram, by asking her to marry him (provided he can get up off one knee).

Alas, the celebrations are shortlived when a drunk Paula totters into the pub and tells daughter Julie to stop making advances towards Colin’s grandson Jason.

What Julie doesn’t know is that she’s groping her nephew. Paula blurts out that Julie and Jason are related because – wait for it – Colin is Julie’s father.

Paula reveals that he seduced her and got her pregnant with Julie when she was 14 (do the maths, then call the police). All of which makes Eileen Grimshaw her sister and Jason her nephew.

Sisterly feelings don’t come into it. And when Colin tries to make amends with Eileen it’s all too much for him.

They argue and he’s rushed to hospital after collapsing. I reckon Rita needn’t bother getting out her wedding dress just yet. Just look at the trouble Becky had on her wedding day. Now she’s trying to become mates with Steve McDonald’s daughter, Amy, to prove she’d make a good mum.

She steps in when Amy is bullied at school but Steve’s mum, Liz, is miffed when the little girl asks Becky to help her with her homework (although I suspect she thinks algebra is a form of breast support). Besides, Liz has never struck me as a Mastermind candidate.

Cain returns to Emmerdale (ITV1) and gets a less than friendly reception from what’s left of the King brothers, Carl and Jimmy.

They’re not happy to see the man who robbed the family of £2.5m.

He agrees he’s a bounder and a cad and invites the brothers to have a pop at him. They oblige by giving him a good beating.

Debbie’s glad to see her father again, but reckons his tough guy methods might be more of a hindrance than a help in gaining custody of her daughter from Handy Andy.

Like father, like daughter.

Debbie shows she’s a chip off the old block over Maisie Wylde, who’s taking Andy’s side in the custody battle. A showdown between Debbie and Maisie turns violent, leading to Maisie being dunked in the horse trough. No horses were harmed in the filming of this scene, although I can’t be sure the same goes for the actresses.

Syed Masood has arrived in EastEnders (BBC1) to show his parents that he’s a changed man.

Which means he really shouldn’t have slept with Janine, who has so many notches on her bedpost that it looks like deathwatch beetle has been on the rampage.

Imagine Masood’s horror when he delivers another kind of post to Janine’s one morning only to find his son is there and he’s not delivering milk. Little does Janine know that Syed already has a girlfriend.

This week’s drunken brawl in the Vic belongs, yet again, to the Mitchell family. Fill the Fug is on the booze and ruins the party for Silly Billy’s 50th. That figure signifies his IQ not his age.